atm resolution is given in width and height (WWWW x HHHH),
Better would be a list of only all widths . There a so many different resolutions with all these big desktop screens, not/net/web-books and phablets and etc, and this is useful for responsive design.
from discussion on http://forum.piwik.org/read.php?3,102629,102716#msg-102716
Keywords: resolution report width