It would be interesting to adjust the data to compensate for day of the week, as well as for the dates that only happen in a few months out of the year. I wonder if the 31sts in that year were all in the middle of the week, or were all on weekends?
However the 7th, 14th, 21st and 28th days aren't always the end of a week (Friday, or Sunday?).
If we make the assumption that it doesn't matter, and the quotas are 'rolling', then surely the same could be said about the monthly quota not ending at the actual end of the month?
If you look at the graphs, the first two days and the 7th day of the month are higher than average. Same for the second week; the 8th & 9th and the 14th days of the month are higher than average.
Also, the 7th, 14th, 21st, and 28th days are all above average.
