Board Thread:Game Discussion/@comment-28401107-20170405125528/@comment-26829117-20170405133635

All races count the same percentage but races that you have won but not won count as events completed. This doesn't affect your percentage complete (i.e. you can't reach 100% without getting gold in all races) but it does affect your calculation.

I haven't looked at this too closely, just noticed it as I was approaching 100%. Maybe in the next update I'll wait until I only have a few races left, run them all but not get a podium and see what happens.