In December 2011, Abbott, Inc. issued $100 million in bonds with a 25 year maturity. The bonds have a $1,000 par value, 7.50% coupon rate, and pay interest annually. At origination, the bonds sold at par. Since origination, the yield to maturity on Abbott's bonds has hovered between a low of 6.35% and a high of 9.75%, they currently have a yield to maturity of 8.50%. It is now December 2017, what is the current yield on Abbott, Inc.'s bonds?