The Stock well company intends to engage in a bond issuance strategy; however, it currently faces uncertainty regarding the prevailing yield to maturity that the market would establish. The bonds will have a maturity period of 21 years, an annual coupon rate of 8.83 percent, and a par value of $1,000. Stock well Inc. Based on comprehensive analysis, it has been ascertained that the market valuation of these bonds would amount to $733 per unit. Could you provide me with the current yield to maturity of these bonds, please?

Please ensure that the answers are rounded to two decimal places and expressed in percentage format.

It is advisable to utilize either Microsoft Excel or a specialized financial calculator.