The stats gathering systems for plugins and themes and core are currently offline for database maintenance. They will be back online as soon as possible.
In the meantime, the stats displayed for these items on org will not be collected and will show zeros for most or all items.
When the issues are fixed, the statistical data will take a day to gather and then redisplay for them.
The systems team is examining the problem at present and will have it back up and running as soon as is feasible.