Vertical colored lines in stats - what do they mean?

Hello.
I've noticed addon's stats graphs have different color vertical lines, green and yellow. What do they mean?

Thanks.

I think the yellow band means that AMO's statistics collection was broken that day, and that data is garbage. See http://blog.mozilla.org/addons/2012/04/23/.

I have no idea what today's green band means.

[clouserw]

If you click on the bands it will tell you what it represents. Green is generally a product release.

Oh I see. Not very intuitive though, would be nice if cursor change to pointer when however over it .
It would be interesting to see another type of line - when addon was updated