Time on Site Metrics Deprecated

Way back on 2014-04-16, Google Analytics changed the “Time on Site” and “Avg. Time on Site” metrics into “Session Duration” and “Avg. Session Duration“. The old metrics continued to work for over 3 years, but as of July 2017, they stopped working.

If your report used the old metrics, you are probably getting errors complaining about “unknown metrics” ga:timeOnSite or ga:avgTimeOnSite. To fix things, edit the report and change the metrics to the new session duration equivalents.