So based on the percentages Xbox 360 sold 800k and is undertracked by 225k and PS3 sold 600k and is undertracked by 95k this year assuming vgchartz numbers from last year are accurate.
Although since the ps4 sold 530k and was ahead of the ps3 from the source that means the ps3 is only undertracked by up to 30k, which means last year it was overtracked by at least 170k and that is assuming it sold 1 less console than the ps4 this year.
So PS3 overtracked by a minimum of 140k from the last 2 years and xbox 360 is undertracked by 225k if last year's numbers are accurate. Which is a big if. Sadly we can't really know for sure about that unless the numbers were announced at some point.
EDIT. So according to this UK console sales were down 34.1% in 2012. According to vgchartz they were down 35% if we adjust last year's ps3 numbers down 170k. So basically either vgchartz tracking is off from all the way back in 2011, or the combined wii+360 total numbers from 2012 are pretty accurate.
http://www.vg247.com/2013/01/04/uk-console-sales-down-a-third-in-2012/
