Methodological considerations for the census design : Technical Session 3 http://www.fao.org/economic/ess/ess-events/wca2020bangkok/en/ © FAO https://www.fao.org

1. Workshop on
World Programme for the Census of Agriculture 2020
Bangkok, Thailand
19-23 September 2016
Jairo Castano
Senior Statistician
Leader, Agricultural Census and Survey Team
FAO Statistics Division
Methodological Considerations
Technical Session 3
1

2. 2
Contents
• Background
• Overview of census modalities: description, implementation
steps, advantages, disadvantages and requirements
1. Classical approach
2. Modular approach
3. Integrated census/survey modality
4. Combined agriculture census with use of administrative
sources
• Country examples

3. Background
• The present Programme broadens the approaches
introduced in the previous one, acknowledging that the
census of agriculture can be conducted in different ways,
using four main modalities:
Classical approach
Modular approach
Integrated census and survey programme
Combined census with use of administrative sources
• Main aim is to help countries to implement a census in
most efficient way, taking into account countries’
particular conditions.

4. Overview of census modalities
i) The classical approach: a census conducted in a single one-off operation
(usually by complete enumeration) comprising the universe of agricultural
holdings. It should cover all essential items and may include additional
items.
ii) Modular approach: comprises: a) a core module undertaken by complete
enumeration including all frame items and eventually other items; and b)
supplementary modules targeting specific populations identified through the
frame provided by the core module.
iii) The integrated census and survey programme: integrates a multi-year
programme of censuses and surveys. One option is AGRIS, a modular
survey programme which has to be articulated with the agricultural
census programme and conducted on an annual basis between two censuses.
iv) Combined census with use of admin sources: registers and other
administrative sources are used as a source of census data in combination
with field data collection.

5. Comparison of census modalities
Classical Modular Integrated
census/survey
Combined
with admin
Enumeration
phases
One-off field
operation
Multiple phases:
a) core module
b) supplementary
module(s)
Multiple phases:
a) census core module
b) rotating thematic
modules
One or more field
operations and use
of admin sources
Coverage of
items
All census
items collected
during a one-
off operation
Core module
includes items
required at the
lowest geo/admin
level, and those to
establish frames for
the supplementary
module(s)
Census core-module
includes items
required at the lowest
geographic/admin
level, and those to
establish frames for
rotating thematic
module(s)
Census items are
collected through
field operation and
use of administrative
sources.
Enumeration
method
Complete
enumeration
exclusively or
combined with
sample
enumeration
Complete
enumeration for
core module and
sample
enumeration for
supplementary
modules(s)
Complete enumeration
for census core module
and sampling
for rotating thematic
modules
Complete
enumeration
exclusively or
combined with
sample enumeration

6. Alternative census modalities
• The classical approach is the most extensively used census
modality. However, more and more countries would use
alternative census modalities in the near future.
• There are important reasons for using alternative census
modalities:
i. budget limitation for census,
ii. need to produce more frequent and timely agricultural statistics,
iii. fast growing digital and mobile technology;
iv. increasing availability and access to data from administrative
sources and technical capacities to handle such data;
v. reluctance of some population groups to participate in the census
and need to reduce respondent burden.

7. Some common issues for any
census modality
• Identify data content of the census:
o The minimum requirement for a census, is to include all essential items,
in order to enable international comparison and frame items for census
modules or/and follow up surveys
o The final list of census items should be established in consultation with
main stakeholders depending on country’s requirements, availability of
reliable administrative and other data sources, financial and other
resources
o In countries with well-developed registers, the use of administrative
data sources (ADS) to cover census data items should be considered .

8. Some common issues for any
census modality (cntd.)
• The frame for the agric. census must be carefully established
to ensure that all holdings are covered with no omissions or
duplications.
•Use of sample enumeration
 efficiency considerations (precision versus costs), other elements should be taken into
account, such as:
 desired level of aggregation for census data
 use of the census as a frame for ongoing sample surveys
 data content of the census and
 capacity to deal with sampling methods and subsequent statistical analysis based on

9. Some common issues for any
census modality (cntd.)
•Use of thresholds
oIn many countries, a minimum size limit is
adopted for holdings included in the census.
oThe rationale for this could be:
in the country there is a large number of very small
holdings which make a marginal contribution to
total agricultural production but
their inclusion in the census greatly increases the
workload and census budget.

10. 1. The classical approach
• May be considered as a census conducted as a
single one-off operation in which all the census
information is recorded. By extension, this approach
also includes the short-long questionnaire concept.
• Should include all “essential” items and may
include “additional” items depending on: a)
country’s requirements; b) other data sources (e.g.
non-structural items); and c) available resources.
• Can be conducted by complete enumeration, sample
enumeration, or by a combination of both.

11. 1. The classical approach (contd.)
This approach is appropriate when countries:
•Wish to conduct a single one-off operation
•Have an integrated census and survey
programme (e.g. no need for supplementary
modules)
•Wish to collect some additional items at low
administrative levels.

12. 1. The classical approach: main
features
• Enumeration is conducted as a single one-off
operation, during a specified enumeration period,
providing a snapshot of the entire population at a
specified period.
• However, certain regions of a country may be
enumerated at different times of the year because
of seasonal and agricultural conditions.
• The classical approach also includes cases where
(under the short-long questionnaire concept) the
long questionnaire is completed at a second visit.

13. 1. The classical approach: ways
and steps for its implementation
The following questions arise:
1) Will complete enumeration be used in exclusivity
or in combination with sample enumeration?
2) If complete enumeration is used in combination
with sampling, what part of the population will be
sampled? Is a reliable sample frame available?
3) Will a single questionnaire be administered to all
agricultural holdings, or different questionnaires,
e.g. will a short-long questionnaire concept be
applied?

14. 1. The classical approach:
complete enumeration
• Exhaustive enumeration of all agricultural
holdings above a threshold (if any).
• It is the most costly and challenging in
terms of planning and organization. It is
much less demanding in respect of the
characteristics contained in the frame than a
sample-based census and is often the most
practical way to conduct a census and build
up a statistical farm register.

15. 1. The classical approach:
sample & complete enumeration
• A part of the target population is enumerated on exhaustive basis
and another part using sample. This method aims at increasing cost-
efficiency but the sampled part will not provide reliable statistics at
the smallest administrative level.
• Ways to combine:
◦ Use complete enumeration in some regions (agriculturally important and/or
easy access) and sample enumeration in other regions;
◦ Use complete enumeration for some types of holdings (large holdings,
commercial holdings or holdings above the threshold) and sample
enumeration for the remaining holdings;
◦ Use of complete enumeration for key census items (such as essential and
frame items) and sample enumeration to collect additional information. This
is a special case of the short-long questionnaire concept.

16. 1. The classical approach: sample
enumeration
• A large sample of holdings (large enough to generate sub-national
data) is selected and enumerated in one-off operation.
• It is less costly in terms of field work and reduces the respondent
burden in comparison with complete enumeration.
• However, a reliable sampling frame with adequate auxiliary
information (e.g. area of holding, number of livestock) is required,
as well as high-level expertise in survey organization and sampling.
• The probability sample of agricultural holdings for sample
enumeration can be drawn from the sampling frame built-up based
on a recent population and housing census, a statistical farm
register and/or other statistical and administrative sources.

17. 1. The classical approach:
types of questionnaires
• Single questionnaire: administered to all agricultural holdings covered
by the census without regard of their type. It is easy to apply in the field.
• Short-long questionnaire: In many cases (mainly when an updated
census frame is not available) the classical approach involves the short-
long questionnaire modality:
­ Short questionnaire administered to screen the target population and collects basic
information on all households and identifies holdings meeting a given threshold;
­ Long questionnaire administered only to holdings identified above the threshold (or to
a sample of such holdings) to collect more detailed information from the holdings.
• Other types of questionnaires: specific census questionnaires to fit
different segments of the target population (such as household and non-
household based holdings). Or for different provinces when these differ
considerably in cropping and livestock systems, and in agricultural
practices.

18. 1. The classical approach: Data
collection from holdings in the household
sector and in the non-household sector
• Two types of agricultural holdings:
- In the household sector - in the non-household sector.
• Special holdings such as large commercial holdings, usually are in the non-
household sector and are “self-enumerated” or interviewed face-to-face.
• The enumeration period for special holdings should be similar to that
established for the other holdings. When self-enumeration methods are used,
census questionnaires should be sent well in advance to allow timely provision
of data.
• Household-based holdings, in developing countries are commonly enumerated
using face-to-face interviews.

19. 1. The classical approach:
advantages
• Provides a snapshot of the entire target population at a specified period and
comprehensive data sets are available at the lowest geographical level.
• Data can be produced at lowest administrative and geographical levels with
no sampling error. Tabulations can be done in line with high user’s
requirements, including data for small administrative units and information
on rare events, such as emerging crops, rare crops and types of livestock.
• When taken with complete enumeration it is much less demanding in respect
of the characteristics contained in the frame than the sample-based census.
• The classical census taken by complete enumeration can constitute a good
basis for building up a statistical farm register and an exhaustive sampling
frame for subsequent regular agricultural surveys.

20. 1. The classical approach:
disadvantages
• Cost and administrative complexity (mainly if it is taken
by complete enumeration);
• It implies a high burden on respondents;
• There is the risk to overburden the census questionnaire
because of the high pressure from some policy makers or
other stakeholders to include detailed items to collect
data at the national level and at the lowest administrative
level;
• Very large number of enumerators and supervisors
required (complete enumeration);
• The amount of data to be processed is larger.

21. 1. The classical approach:
requirements
• Good organization capacity and planning.
• Sufficient and timely budget allocation during census
preparation, field operation, data processing & dissemination
needs to be ensured.
• Availability of sufficient number of qualified field staff.
• Involvement of all relevant public authorities, in particular at
local level, is essential for successful field operations
(enumeration, publicity campaign).
• If the classical census is conducted on sample basis, additional
requirements are:
Availability of a good survey organization capacity of the
census agency, including adequate sampling expertise.
Availability of a reliable sampling frame.

22. 2. Modular census: main
features
• This modality has a clearly distinguishable core module (on a
complete enumeration basis) and one or more supplementary
modules (on a sample basis).
• An essential condition: data from the core module used as
frame for the supplementary module(s). The census using the
short-long questionnaire in one operation is not considered as
modular census (no frame use).
• A ‘module’ is defined as a group of data items to be collected
on a specific target population (e.g. holdings with livestock).
• All essential items should be covered by the core and
supplementary module(s).

23. 2. Modular census: main
features (contd.)
• Core module must include the items required at the lowest
geographic or administrative levels, and/or needed to establish
sampling frames for the supplementary module(s).
• The core module should include all frame items. This module
should also cover rare events (unusual crops or livestock), which
would not be possible to estimate from supplementary modules
conducted on sample basis because of high sampling errors.
• Supplementary modules use the frame generated by the core
module to target specific populations and should include the rest of
the agreed census items that are not included in the core module.

24. 2. Modular census modality: ways
and steps for implementation
• Two ways of implementing the modular approach:
i. implementing core and supplementary modules
separately
ii. implementing the core module and the supplementary
module(s) as part of a single data collection operation
(difficult in practice).
• Sources of frame data for supplementary modules:
a) The census core module;
b) An agricultural module/section of the population census;
c) Administrative registers.

25. 2 a). Core module with complete
enumeration as frame for supplementary
module(s)
(i) Implementing core and supplementary modules separately. It implies two
phases:
 Phase 1: the core module is first implemented and questionnaires are returned to the office for
processing and building frame (s) for the supplementary module(s);
 Phase 2: enumerators return to the field to carry out the census supplementary module(s) on the
selected sample (s) of holdings for the module(s)
(ii) Implementing the core module and the supplementary module(s) as part of a
single data collection operation. It implies:
 Collect data for the core census module;
 Apply specific sampling procedures, based on responses to the core module questions, to
determine holdings to include in the supplementary module(s);
 If the holding is included in the sample for the supplementary module(s), proceed to apply the
supplementary module(s). Otherwise, the interview is finished.

26. 2 b). Modular census: Agricultural
data from a recent population census
as frame for supplementary modules
When an agricultural module/section is included in the
population census, two possible situations arise:
Only few agricultural items were included in the population census,
not enough to provide frame items needed for all supplementary
modules. In this case, a lighter core module is needed to collect missing
frame items and any other item suitable for the core.
Most of the frame items have been collected in the agricultural
module/section of the population census. Therefore, the country may
use this information to implement the supplementary modules.

27. 2 c). Modular census :
Administrative sources as frame
data for supplementary modules
• In countries where administrative data is well
organised and of good quality data may be
available to provide a large proportion of all
essential data items, including frame data for
supplementary modules.
• This information can be therefore used to
implement one or more supplementary modules
to collect the rest of the essential data or specific
data of interest to the country.

28. 2. Modular census: special
holdings
• In the modular census, special holdings (large commercial farms,
holdings in the non-household sector, etc.) may be covered during the
first or second phase field operation (supplementary modules).
• All required information (core and supplementary) should be collected
in one operation only by dedicated staff using a specific questionnaire
for such holdings. The timing will depend on the availability of
dedicated staff for collecting the data.
• Efforts should be made to cover these special holdings as closely as
possible to the implementation of the core module in the household
sector to ensure that the same reference period is used for all items
collected.

29. 2. Modular census modality:
advantages
• The combination of core and supplementary items allows the modular
census to produce a more extensive and country-specific range of
data compared with the classical census modality, for which small
area estimates are not important.
• More effective use of available budget to collect country relevant
information.
• Allows a focused and more detailed training of field personnel.
• Countries with a not well established system of agricultural surveys
and limited budget may find the modular approach as a logical first
step towards the creation of a system of integrated agricultural
censuses and surveys.

30. 2. Modular census modality:
disadvantages
• Risk of having a core module with too many items (due to pressure from stakeholders) at
low geographical level.
• The lack of well trained professional staff in sampling.
• If supplem. modules are undertaken at the same time as the core module there exists the
risk of loss of data quality if not properly organized.
• There are limitations in terms of cross-tabulation between variables in the core and in the
supplementary modules or between variables in different supplementary modules not
conducted jointly.
• If the time lag between the implementation of the core and supplem. modules is too long,
the benefit of having a good frame from the core module disappears. An frame update
would be needed adding to the cost.
• If the core module is largely covered in a population census it could be difficult to
mobilize additional funds for supplementary modules.
• In the absence of a rigorous programming, the conducting of the core module and
publication of results can jeopardize a better preparation of complementary and thematic
modules.

31. 2. Modular census modality:
requirements
• Good planning and survey organization capacity, including minimum
sampling expertise.
• Adequate budget allocation between core and supplementary modules
• Capacity and resources to conduct core module and supplementary modules
with a short time lag
• Availability of field staff with minimum level of qualification that can be
mobilized to conduct sometimes complex surveys for supplementary modules
• A good cooperation and coordination of census activities between interested
institutions and good partnership in the organization of a comprehensive
census publicity communication/public awareness campaign.

32. 3. Integrated Census/survey
modality
• This new modality features a census core module (to be conducted
on a complete enumeration basis) and a number of several rotating
thematic modules (to be conducted annually or periodically on
sample basis over a 10-year period). An example of rotating
modules is the new Agricultural Integrated Survey programme
(AGRIS).
• The recommended data items to be covered in this census modality
are the same as all other modalities (essential, frame and additional
items).
• The census core module should mainly provide frame data needed
to implement rotating thematic modules.

33. 3. What is AGRIS?
• The AGRIS is a modular survey program which is to be
articulated with the agricultural census programme and
conducted on an annual basis between two censuses.
• It consists of one annual core module (crop and livestock
production) and four rotating modules: ‘economy’,
‘labour force’, ‘machinery and equipment’, and
‘production methods and environment’. Additional
modules can be added as needed.
• In the integrated census and survey modality, AGRIS is
synchronized with the agricultural census core module
and operates over a 10-year cycle.

34. Example of possible modules and timing of their implementation (illustration)
POSSIBLE MODULES
YEARS
1 2 3 4 5 6 7 8 9 10
Agricultural census core module (and AGRIS core module
where relevant and possible)
•
AGRIS Core Module
Crop production  • • • • • • • • •
Livestock production  • • • • • • • • •
AGRIS Rot. Module 1 Economy • • • •
AGRIS Rot. Module 2 Labour force • • •
AGRIS Rot. Module 3 Machinery and equipment • •
AGRIS Rot. Module 4
Production methods and
environment
• • •
3. Integrated Census/survey
modality: illustration
 denotes optional implementation in year 1

35. 3. Integrated Census/survey modality:
ways and steps for the implementation
• The implementation of the integrated
census/survey modality will start with a census
core module (on a complete enumeration).
• As with other modalities, there could be three
sources of frame data for the rotating thematic
module(s):
a) census core module (on complete enumeration)
b) An agricultural module/section in the population
census
c) Administrative registers

36. 3 a). Integrated census/survey modality:
census core module as frame for rotating
thematic module(s)
• The census core module and the rotating thematic modules will be conducted as follow:
• During the first year the census core module is implemented through complete
enumeration. The frame data collected is processed and analyzed to build required frames
for the subsequent rotating thematic modules and AGRIS core module.
• The frame is used to design the surveys that will be implemented in the following years
to collect data for the rotating thematic modules and AGRIS core module until the next
complete enumeration exercise.
• From year 2, AGRIS core will be implemented annually while each rotating thematic
module will be implemented every 2 or 3 years. Therefore, each year there will be a
survey covering AGRIS core and one or more rotating thematic modules. Annual surveys
will therefore be a combination of farm structure data and current production data
providing continuous flow of data and allowing more frequent update of some structural
information.

37. 3 b) and c). Integrated census/survey
modality: population census and
admin sources as frame for
rotating thematic modules and
AGRIS core
• Similar to earlier modalities.

38. 3. Integrated census/survey
modality: advantages
• Effective use of available budget to collect
country relevant information on an annual basis
• More detailed information available on topics of
interest
• Focused training of field staff
• Wider set of census items
• Decisive step towards the establishment of a
system of integrated censuses and surveys

39. 3. Integrated census/survey
modality: limitations
• The risk of expanding too much the census core module resulting in
high cost which will reduce the relative benefits of this census
modality.
• The challenge of conducting the census core module and AGRIS core
at the same time (when relevant). This requires good survey planning
and sampling capacity.
• The limitations in terms of cross-tabulation between variables in the
core and in the rotating thematic modules or between variables in
different rotating thematic modules not conducted jointly.
• Difference in the reference period for different census items collected
in the census core and the items in the rotating thematic modules.

40. 3. Integrated census/survey
modality: requirements
• The need for maintaining and updating the sampling frame
is critical as the frame becomes gradually obsolete over
time.
• A mechanism should be put in place to ensure its validity.
• It requires well trained personnel in sampling methods, an
additional cost.
• It requires a continuous flow of resources. In countries
where funding is mainly from external sources, there may
be budgetary and other administrative constraints for
commitments over such a long period as 10 years.

41. 4. Combined agriculture census with
use of administrative sources: main
features
• A meaningful part of the census items for the
entire population of the census of agriculture (or
for part of it) comes from existing administrative
sources created for non-statistical purposes.
• The data could come from one or several
administrative sources. It could be also used in
combination with field data collection.

42. 4. Combined agriculture census with
use of admin sources: main features
(contd.)
• An important feature of the data from administrative sources is that
the information is not primarily collected for statistical purposes.
• Administrative sources may be for selective items or may target a
specific population.
• Thus the definition of the population of interest and the data collection
protocols is out of the control of the census office.
• There is a substantial difference in the organisational approach of the
census when using administrative data as compared to other
approaches.
• As the objects already exist in the data source, a selection need to be
made of objects (holders or holdings) and variables that are relevant to
the census.

43. 4. Combined agriculture census with use
of admin sources: Quality considerations
• Some information in administrative sources could be of low importance for administrative
purposes which may result in lower statistical quality.
• The purpose and method used to collect data should also be taken into account to detect
possible systematic errors or systematic bias in the register
• The following quality aspects need to be carefully considered:
­ Relevance (content) of the administrative data sources.
­ Accuracy: an admin source is of good quality if a large proportion of the variables
required for the census exists in the register and corresponding data are reliable.
­ One important accuracy category is related to the data coverage: under-coverage or
over-coverage of units, multiple listings, and misclassification of items.
­ Completeness
­ Unreported events: data related to the reference period is not available in the source
referring to an event from which parameters are to be derived: e.g. births, deaths or
loss, sales, etc. of livestock.
• The information from administrative sources has to be coherent and comparable with
data from other sources or over time.
• The timeliness dimension (difference between the reference period and the availability of
the results) when using administrative data source.
• Accessibility in terms of physical access to the information in the admin source.

44. 4. Combined agriculture census with
use of admin sources: Ways of
using admin data in this modality
1. The starting point (like in all census modalities) is to define the data content of the census in terms
of data items to be covered.
2. Next step is to decide on the way to use the admin source. Possible ways or approaches are:
 Split data approach: admin sources are used to provide some of the variables for all of the
holdings.
 Split population approach: Data from admin sources are used for some holdings where these
data are of sufficient quality, and other statistical sources are used for the remainder of the
holdings.
 Combining the two approaches: administrative sources replace the field data collection for
some of the variables for part of the holdings.
 Pre-filling answers in the questionnaires which are to be checked by respondents during the
census.
 Totally replacing the census data collection, on all census characteristics and for all units in the
census population with data coming from one or more admin sources (no very common).

45. 4. Combined agriculture census with
use of admin sources: Steps for
implementation
1. Assess the usability of the source/register;
2. Detailed analysis of the quality of the administrative source in terms
of:
 Legal basis: Analize the kind of legislation needed to allow access to,
transfer and use of administrative data at unit level for statistical
purposes.
 Consultations between owner and user organizations to understand the
opportunities and difficulties: Which definitions were used? What is the
scope? What is the coverage; Which are the reference periods; What are
the identifiers used? etc.
 Public support: It is important to make clear the differences between
statistical and non-statistical utilization of administrative data files both in
professional and public groups of society.

46. 4. Combined agriculture census with
use of administrative sources:
Steps for implementation (contd.)
 Design a government-wide project well in advance as a good
organisational way to outline responsibilities and the necessary work:
 Make an inventory of all available admin data sources including the
evaluation of its content in terms of usability and quality.
 Develop the content and the conceptual framework for the utilization of
administrative records for the census.
 Decide what items are to be produced from what kind of data sources.
 Determine step by step how the data sets are to be prepared for
interconnection / linking.
 Develop the synchronization relations of information systems and the
commonly accepted data management and data security regulations.
 Plan the budget for the particular preparatory work related to the use of
administrative sources for the agricultural census

47. 4. Combined agriculture census with
use of administrative sources:
Advantages
Reduction of cost of census data production;
Reduction of the burden on respondents;
By combining the data collected in the field with the data from administrative
sources, new derived variables can be created;
It allows compilation and publication more frequently and faster;
Non-response rate can be either significantly reduced or eliminated (when data on
the entire target census population is included in the administrative sources);
It could significantly improve the quality of the source and leads to a substantial
harmonization of certain information between different institutions.
 As a result of more efficient and faster operation the public perception of
statistics may become more favourable.

48. 4. Combined agriculture census with
use of administrative sources:
disadvantages
Linkage of data sets can be difficult (or impossible) if legal background is unclear;
It could be very difficult to establish a good cooperation with register owners;
The cost for the access to the admin data could be too high.
When there is different population coverage, admin sources can be used for pre-filling the
questionnaires only on common population while other units need to be enumerated;
Incoherence of concepts, definitions, classification and reference periods could hamper the
use of admin sources;
Problems related to linking data from various data sources;
Problems on quality or risks concerning stability may arise due to political changes;
Timeliness and punctuality;
If an admin source is abolished, it is difficult to provide comparable statistical data series;
Substantive or technical changes in the admin sources may not be detected immediately;
Comparability over time is strongly influenced by the change in the level of coverage in
the different years and can give misleading results.

49. 4. Combined agriculture census
with use of admin sources:
requirements
Availability of relevant Registers and Administrative database/s with good quality data at
individual holding level, clear and harmonised definitions and appropriate frequency for data
update
Availability of sufficient competent experts with good IT infrastructure knowledge and
database management skills at the initial stage of the census preparation.
Existence of an Agreement established between the census office (user) and administrative
body (owner) defining methodological and technical details about the access and use of admin
sources.
Public appreciation of the benefits of using register sources for statistical purposes.
Availability of a good legal basis and governance infrastructure, involvement of public
authorities and administrative sources owners, and an established system for data control.
Good IT infrastructure;
Unified identification system through all data sources.

50. Country examples
Uruguay National Agricultural Census 2011:
Classical approach, complete enumeration, one-off
operation
•The total agricultural area of the country (163,572 km2
out of a total country surface of 176,000 km2
) was
divided in 637 enumeration sectors that were canvassed
during 4 months taken information from 44,781
agricultural holdings of 1 ha and over of total area.
•An unique census questionnaire was used containing
12 sections and more than 250 questions.

51. Country examples
Gambia 2011-2012 Census of agriculture: sampled-based census.
•The 2011/2012 Census of Agriculture was a sample survey of
approximately 15% of rural households in the 2003 Census of Population.
•The sampling design was a stratified two-stage design with districts
forming the strata and the first-stage units being the EAs. First stage units
were selected systematically in proportion to the 2003 total number of
households. The second-stage sampling units were the holders (of
agricultural holdings) within EAs from which a systematic random sample
of five (5) holders was selected for enumeration.
•The enumeration period spanned for 7 months.
•Seven structured questionnaire forms were used (listing, demographic, area
measurement-GPS, harvest, community, groundnut, mango).

52. Country examples
Bangladesh Census of Agriculture 2008: Modular approach.
The census was taken in two phases:
• First phase (11-25 May 2008) for the core module (complete enumeration);
• Second phase (15 Nov - 4 Dec 2008) for the supplementary modules (on
sample basis).
The core module covered all households managing more than 0.05 acres of
land. It comprised all recommended items for the core module in the WCA
2010 Programme.
Six supplementary modules were undertaken by means of a long
questionnaire applied to a sample of holdings identified during the core
module and classified in “small”, “medium” and “large” holdings. The
supplementary modules were:
 equipment and farming system;  agriculture employment;
 irrigated area under crops;  stock of livestock and poultry;
 agriculture credit;  agriculture implements.

53. Country examples
Netherland Agricultural Census 2010: Combined agricultural census
with use of administrative registers.
•The agricultural census frame for the AC 2010 was the administrative farm
register (AFR) of the Ministry of Economic Affairs, Agriculture and
Innovation. Farmers have to register by law. The AFR contains names,
addresses and other characteristics of holders or holdings and a unique
registration number.
•The agricultural census applies a higher threshold than the AFR, thus only
agricultural holdings above the threshold are taken into account.
•This threshold is applied to separate professional from hobby farmers, and
to minimize processing burden.
•Information on the census items existing in the AFR is taken directly from
the register for the whole census population.

54. MANY THANKS
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