It appears that we stopped accurately logging most Echo events on January 16, 2014
See: http://ee-dashboard.wmflabs.org/dashboards/enwiki-features
SELECT MAX(timestamp) FROM Echo_6081131 WHERE wiki = 'enwiki' AND event_notificationType = 'reverted';
20140116190505
SELECT MAX(timestamp) FROM Echo_6081131 WHERE wiki = 'enwiki' AND event_notificationType = 'edit-thank';
20140116190354
Version: unspecified
Severity: normal
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=60550