The cost of the items in “The Twelve Days of Christmas” grew by only 0.6 percent in 2015 — "reflecting a steep decline in energy costs, lower inflation and slow-but-steady economic growth," PNC Financial Services Group Inc.(NYSE: PNC) reported. To buy your true love one of each of the items offered in the traditional Christmas carol, it would cost you $ 34,130.99, according to the annual PNC Christmas Price Index conducted by PNC Wealth Management.