Robrotron, Inc. is considering the installation of a new robot that costs $145,000. This robot is expected to save them $32,000 per year in labor costs for the next 15 years. Maintenance costs are expected to average $8,000 per year. Use straight-line depreciation and assume $0 salvage value. The total income tax rate is 34% (federal, state, and municipal). What is the after-tax rate of return for this mechanism?