Windows 7: how to split "a long time ago" group

I have a folder, which includes a lot of files from 2006, 2007, 2008, 2009 and 2010. When I use the Group by > Date modified to categorize the files, it puts everything before 2010 in a group called "a long time ago" which is not helpful at all. I'd prefer it group the files at least by year, say a group for 2009, another for 2008 and such. What is "a long time ago" anyway??? Vista had the same group for all of the not-so-recent files, and I was expecting 7 to have a better grouping, but I think it doesn't. Or is there really a way -that I don't know- to split "a long time ago" group into subgroups?