Great Seneca Inc.sells $100 million worth of 23-year to maturity 6.69% annual coupon bonds. The net proceeds (proceeds after flotation costs) are $980 for each $1,000 bond. The firm's marginal tax rate is 40%. What is the after-tax cost of capital for this debt financing?

Round the answer to two decimal places in percentage form.(Write the percentage sign in the "units" box)