- Plesk 11.x for Linux
- Plesk 12.0 for Linux
Awstats does not calculate statistics properly for the last day of every month.
This is Plesk bug with ID #PPPM-1486 and was fixed in micro-update #10 for Plesk 12: 12.0.18 MU#10
Install latest Plesk updates via Home > Tools & Settings > Updates & Upgrades menu.