PNC Wealth Management released its annual “Christmas Price Index” Monday, which calculates how much it would cost to buy the gifts in the Christmas carol “The 12 Days of Christmas.” If one’s “true love” bought all of the gifts mentioned in song’s final verse, then the bill would come out to $34,130.99, up from $33,933.22 in 2014 — making 2015 the priciest year yet.