Services on our DEV server are slow and I would like to figure out why using the statistics reports in ArcGIS Server Manager. But the reports I see are empty, unlike those in our TEST, ACC and PROD environments (see picture below). I have checked the ArcGIS Server Administrator Directory and all settings for usage reports are identical in all environments (see second picture below). Any idea why?
We use ArcGIS for Server 10.3.1 on a Windows Server 2012 R2 Standard.
I've also asked this question on gis.stackexchange.com.