Most credit card interest rates are pegged to the Prime rate — and traditionally, they have moved up or down in synch with it. In the past few years, though, that hasn’t been the case. Just the opposite: as the Prime rate has dropped from 7.75% in 2007 to 3.25% in 2011, the average credit-card APR has increased from 11.5% to 14.65%. Why are credit-card rates going through he roof? This infographic gives you the answer.