Mr. Krabs doesn't like the idea of being in debt, so he decides to add $200 to his monthly mortgage payment to pay it off sooner. His previous mortgage payment was $1,470/month for 20 years at 8%, and the cost of the home was $175,744.81. By adding $200 to his monthly payment, approximately how long will it take him to pay off his mortgage? (hint: solving for NPER, round your answer to the closest number of years)