Google AdSense Report, buggy?

[imported_LoKe]

If I check my AdSense reports for today, it says 2,590 page impressions. If I choose "all of August," it says 2,333 page impressions.

Is that a glitch/bug, or is there a reason why my monthly results would be lower than todays?

EDIT: Copy and pasted the same numbers. Fixed.