Mine is high as well but just in the upstream so I can't complain lol
on the downstream (from the exchange to the router), if the errors seconds is > 500 few minutes after rebooting and the HEC (header error control) is > 20
this is means that there is a possible fault somewhere.

It also depends on whether you are on an interleaved connection or not. That sort of ES rate on a non-interleaved line is likely to be a big problem. I wouldn't be too happy with that sort of ES rate even on an interleaved line either. In fact that sort of ES rate over an hour would bother me, never mind a few minutes!