Its the weekend!! Correct me if i'm wrong, but I believe trading volume goes up on the weekends
I will be looking at which day of the week and what time during the day that trading is the heaviest. I will post once I am finished.
I think your findings will be inconclusive. Day of the week, beginning/end of the month, Holidays, Tax season (in USA), etc. There are too many variables to say "Wednesday is the day to sell, and Saturday is the day to buy".
Just my hypothesis.