Over at Search Engine Land Danny Sullivan has used the Olympics as a Google Suggest example.
Look at the match count for Olympics 2012 and Olympics 2016. The 2016 tally hits 1,080,000 whereas London's 2012 only makes 738,00. That puts 2016 at about 46% higher.
Of course, the actual search results don't match up. An actual search on [Olympics 2012] comes up with 2,030,000 matches whereas [Olympics 2012] hits 2,100,000.
The same search with exact match/quotes gives 2012 a total 533,000 of and 2016 32,600 hits.
Looks like 2016 is a more popular year than 2012.