Not sure how this will go and not sure if this is going to confirm your figures but lets see:

It is Day, Favs, Payout on Betprice, Payout on layprice

Friday	1043	1077.12	1100.29
Monday	679	622.77	638.22
Saturday	2337	2383.48	2474.72
Sunday	1751	1661.79	1711.88
Thursday	1176	1147.92	1178.1
Tuesday	756	761.41	784.75
Wednesday	1217	1194.66	1222.2

Best days to lay favs are Monday and Sunday.


The only filter applied is to exclude maidens.