looks like the reputation graph on stackoverflow only shows finished full weeks and not up to current date. confirm? is it a feature or a bug?
Basically I just realized that the date window in the graph and the input fields below don't always match exactly.
Today's (2011/01/20) screenshot is quite fine. The graph is up to 2011/01/19 where as the input field implies 20111/01/20.
Yesterday when I opened the question my graph was up to 2011/01/15 and the input field for end date 2011/01/19.
The end date input field value defaults always to "today" but the end date shown in the graph is behind. Over the last 2 weeks I've recognized such small differences from one day / several days / up to near one week.