The By year category is a reference-only view that displays the yearly data for each type of event. Statistics in this view are generated from the totals that are in the By event view. Any changes to the event records will reflect in this view. The statistics this view displays are the number of times the event occurred in a given year and the total and average attendance for both members and non-members in that year.
The view can be reached by opening the Attendance module, clicking on the Events tab, and clicking on the By year category.