FWIW, because of your comment about "before 2011", I was purposely looking at data from 2008, to help control for that (when the iPhone wasn't yet that popular as the original device kind of sucked; the 3G had just come out, however, as had the App Store, so things were already on an uptick).
Looking at data from 2007, it seems like Apple was spending a third what Microsoft was on marketing, and had half the revenue; arguably then, Apple was spending 33% less than Microsoft on advertising per revenue, not really "a fraction".
However, you seem to be correct about now: I pulled some 10Q's from this year, and it seems Microsoft is spending $3.4b/Q for $17b/Q in sales ($6b/Q profit) while Apple is spending Apple is spending peanuts (although I honestly couldn't find the data I needed to verify this from the 10Q) for about $35b/Q in sales ($9b/Q profit).
While looking into that further (as I was especially bothered that I couldn't find the exact advertising numbers), I then came across this article, which looks at yearly data and comes to the same conclusion.
http://www.forbes.com/sites/ycharts/2012/08/02/who-spends-mo...
