Sauna Company has average invested capital of $900,000 and a target ROI of 20%. The company determines its markup percentage based on absorption costing. Manufacturing costs per unit are as follows: direct materials $6, direct labour $8, variable overhead $2, fixed overhead $2. Unit sales are expected to be 40,000 next year. Total selling and administrative costs are expected to be $360,000. What is Sauna's mark-up percentage ?