Matt Ygelsias breaks it down at Slate:
Back in September 2001, annual per capita disposable income was $27,147, and a whole turkey cost $1.162 per pound. (None of these numbers has been adjusted for inflation, so as to isolate turkey inflation from larger price trends.)….
Here in the fall of 2011, per-capita disposable income is up to $37,088, but frozen turkey costs $1.676 per pound, meaning you could buy scarcely more than 22,000 pounds worth of whole frozen birds.
But even with the rising cost of Turkey in general, every November, Turkey demand goes through the roof and prices go down as classic capitalistic competition to snag the most customers ensues. Compared to the rest of the season, the actual cost now for Turkey should be about 10% cheaper, according to Yglesias.