Some credits also ask for the most recent annual data available, which is referred to as "performance year" data. This may be data from a continuous 12-month period, or, in some cases, may also be an average of several years worth of data.
The STARS Technical Manual provides specifics for each credit, for example:
Report the most recent data available from the three years prior to the anticipated date of submission. Institutions may use the most recent single year for which data is available or an average from throughout the period. Institutions may choose the annual start and end dates that work best with the data they have (e.g. fiscal or calendar year), as long as data are reported from a consecutive 12-month (or 3-year) period.