Weekdatum

Weekdatum is a data point that represents a value tied to a specific calendar week. In analytics and data warehousing, measurements or metrics are often aggregated at weekly granularity, yielding a single datum per week that can be used in trend analysis and reporting.

Identification and granularity: A weekdatum is typically identified by a year and a week number, often following the ISO 8601 standard, where weeks start on Monday and Week 1 is the week with the year's first Thursday. The week can be anchored to a particular date, such as the week’s end (for example, Sunday or Monday), depending on convention.

Construction and aggregation: A weekdatum can be a sum, average, maximum, minimum, or any other aggregation of daily values within the week. When converting daily data to weekly data, analysts choose an aggregation function and ensure that all daily observations within the target week are included consistently.

Applications and issues: Weekdatums are used in business metrics, sales reporting, web analytics, and operational dashboards to reveal weekly patterns and compare performance across weeks and years. Common challenges include handling weeks that straddle year boundaries, time zone differences, and missing days within a week that affect the chosen aggregation method.

Example and related terms: For instance, a weekdatum for 2025-W05 might represent the total sales recorded from Monday of the fifth ISO week to the following Sunday. Related concepts include time series, time dimension, ISO week date, and data aggregation.