I received an email this week from Stephen Dubner over at Freakonomics regarding a post he was writing. Stephen posed a very interesting question… could our data shed any light on whether interest in 9/11 has diminished the remembrance of Pearl Harbor.
I provided the following chart showing the volume of queries (U.S.) for “pearl harbor” and “9/11″:

One of the interesting facets of this chart that some Freakonomic Blog readers picked-up on is the seasonality of “pearl harbor” queries. The repeating pattern of peaks in spring and drop-off each summer, coupled with Wikipedia as a top site receiving traffic fro the term is indicative of educational queries.
The other interesting point in Stephen’s post was whether variations of 9/11 queries when aggregated would surpass pearl harbor queries. Using a custom category of the top 9/11 sites, I found the most common 9/11 queries and updated the chart. The results are below:

It appears that during the school year, particularly in spring, Pearl Harbor queries outpace those for 9/11. Thanks for the interesting question Stephen.