observationyear

Observationyear is a data field used in statistical and research datasets to indicate the calendar year in which a given observation or measurement was recorded. It is commonly represented as a four-digit year (for example, 2015) and can be stored as an integer or a string depending on schema requirements. In many datasets, observationyear is derived from a complete date field, such as observation_date, by extracting the year component.

The concept is widely applied across disciplines, including ecology, epidemiology, social sciences, economics, and environmental monitoring. It supports time-based analyses such as annual trends, cohort grouping, and cross-source alignment, and it is often used for labeling, filtering, or aggregating data by year. In practice, observationyear is sometimes used alongside related temporal fields like month, day, or quarter to enable finer granularity while preserving a clear yearly reference.

Data quality considerations include ensuring consistency in how the year is extracted or stored, handling missing dates, and clarifying whether fiscal year or calendar year is intended when such distinctions exist. When only partial dates are available, practitioners may rely on the earliest or latest possible year or flag records with uncertain year information. In database queries, the year can be obtained from a date field via functions that extract the year component.

See also: year, date, timestamp, fiscal year, time series.