Mined for 6 hours and not find any block with Dual E5 2630 v3 ~ 61Kh/s http://prntscr.com/i7xy0c why estimate 30 CRDS/day?
Estimation is just estimation. You can mine for 95 hours and find nothing then you can find every 5 minutes for next hour. The estimation is only somewhat close to correct over the long time.