Exchange Performance Counters

I am looking for up-to-date information for Exchange 2010/2013/2016 and what each performance counter is and what its threshold should be for a warning.  I am using SolarWinds to monitor my Exchange environment and it is complaining that the counter MSExchange Calendar Attendant\Requests Failed is at 1 not zero. I have seen a few conflicting post. 

This Technet article says 100 and this Technet article says it should be a 0 . 

Any help would be great Thanks