Depreciation is the permanent reduction in the value of an asset over time due to wear and tear, exhaustion, obsolescence, accidents, or depletion. Common methods for calculating depreciation include the straight line method of uniform charges over time and the diminishing balance or reducing balance method of higher charges initially that decline over time.

1. Depreciation
Depreciation is the permanent and continuing
diminution in the quality, quantity or value of
an asset.

2. Causes of Depreciation
Wear and tear
Exhaustion
Obsolescence
Efflux of time
Accidents

3. Depreciation
Depletion
Amortization
Dilapidation

4. Methods of Depreciation
Uniform charge methods
Fixed installment method/Straight line method
Declining charge methods
Diminishing balance/reducing balance/written
down value method
Other methods