Its not percent of a percent. It&#x27;s percent of an absolute change.<p>1st derivative vs 2nd derivative.<p>Edit: hmm, maybe I misunderstood your point. I don&#x27;t think the politifact or qz YOY data from 2009 is based on 2008 (but rather, 2007 [technically not YOY then]). How would they have calculated the YOY without the absolute number for 2008?