Definition
This measure is the share of listed WordPress plugins whose most recent release is two years old or older. It is measured as of a stated date. It marks plugins that have gone without any new version for an extended stretch. It uses each plugin's own last recorded release date, not an average across the group. The two-year line is applied the same way to every plugin measured.
Population and window
Rivale measures this across the whole directory, meaning every plugin listed on WordPress.org on the issue's data date. It also reports the top 12,500 plugins as a separate figure. The window is a single date, the last day of the report month. Both figures use the same stated date.
How it is computed
Plugins whose last release date is 24 months or more before the stated date, divided by the plugins listed on that date. Reported for the whole directory and for the top 12,500 separately. Plugins that report no update date stay in the count of listed plugins and are not counted as two years without an update.
How to read it
A plugin only needs one release inside the two-year window to drop out of this figure, however small that release was. Read it beside update rate for a shorter, monthly view of the same release activity. Read it beside old PHP, no updates to see how a lack of recent releases lines up with a declared PHP version. Comparing the whole-directory share with the top 12,500 plugins share can show whether stale plugins are more common outside the ranked set.
What it is not
This measure does not say a plugin is abandoned, broken, or unsafe to use. It only says its last recorded release is two years old or older on the stated date. It does not account for plugins removed from the directory before that date. It does not measure how far past the two-year line a plugin sits, only that it has crossed the line. It is not the same figure as old PHP, no updates, which adds a declared PHP condition on top.
Related measures
Update rate, Old PHP, no updates, Plugin support for WordPress versions