Bonds issued by Fairfax Mechanical were priced at 902.26 dollars six months ago and are priced at 887.38 dollars today. The bonds have a face value of 1,000 dollars, pay semi-annual coupons, and just made a coupon payment. The bonds had a percentage return over the past six months (from 6 months ago to today) of 6.41 percent. What is the coupon rate of the bonds?