The spikes on the graph for gingerbread at each Christmas is noise which you could have avoided by adding "android" to each search term. Result: http://www.google.com/trends/explore#q=jelly%20bean%20androi...
Wanted to post this comment along with it (but that unfortunately wasn't posted): 'Did not take very long, but I had to smile when I realized why there's a heart beat pattern for "gingerbread".'