Monday, Monday...so good to me?

From 1/20/04 to 1/6/06, average number of new highs for each day:
Monday/first day of the week: 110
Tuesdays: 96
Wednesdays: 96
Thursdays: 93
Fridays: 97
On days during which Monday is closed, Tuesday treated as Monday.
On days during which Friday is closed, Thursday treated as Friday.