% Gave Up Pkts on WS5100 v3.2

I have a site with several issues and noticed that the % Gave Up Pkts on several APs (AP300 internal) is very high, 100% up to 600%.  My question is what is this error really telling me and what is an exceptable limit as I have also seen some APs at 40% - 80% and some as low as 7%.  The AP that had 800% was changed out and the issues in its area went away.  They are using formware  The issues at the site is a high rate of dropped packets on both data and voice.