well, i don't have sales data at hand, but googles ngram viewer has this to say http://books.google.com/ngrams/graph?content=hats%2Ccars%2Chat%2Ccar&year_start=

well, i don't have sales data at hand, but googles ngram viewer has this to say http://books.google.com/ngrams/graph?content=hats%2Ccars%2Chat%2Ccar&year_start=1800&year_end=2010&corpus=0&smoothing=3 http://books.google.com/ngrams/graph?content=hats%2Ccars%2Ch... (no correlation, at least in books)