Formative assessments are used during instruction to adjust teaching to meet student needs, examples include observations and anecdotal records. Summative assessments are given at the end of a year to determine proficiency in tested areas, such as the Discovery Education Test. Diagnostic assessments identify specific difficulties, and should only be used if more contextual measures can't provide the needed information. Progress monitoring assessments periodically show if interventions are successful by demonstrating appropriate growth. Outcome measurements are administered in groups at the end of the year to determine adequate yearly progress of districts, schools, or subgroups.