Google Ngram: Baseball vs Football

Google introduced a new app associated with Google Books, and besides tracking the usage of ketchup and catsup I decided to see which has been referenced more, "baseball" or "football".  Given how the media talks about how football has supplanted baseball as "America's Game", I was surprised to see the the graphical output.

http://ngrams.googlelabs.com/chart?content=football,baseball&corpus=5&smoothing=3&year_start=1900&year_end=2000

The chart shows only the frequency each word is used, and overlooks context.  I would agree that professional football has taken the title of "America's Professional Game" from professional baseball, but I could see an argument that the growth of professional football has come at the expense of college football, and not at the expense of professional baseball.  Because when you think about it, with baseball attendance at or near historic highs and with overall television viewership at an all-time high, too, I would argue that baseball continues to maintain a strong position within American sports psyche...