Carl has a credit card with a balance of $5,260 and an APR of 21%. With the monthly payments he has been making, Carl would be able to pay off his credit card in 18 months. After receiving a promotional offer in the mail, Carl decides to transfer his balance to a new credit card with a 15% "introductory" APR for the first 12 months. After 12 months, the APR increases to 23%. How much will Carl save in finance charges (interest) if he pays off the credit card before the introductory APR expires?