A present asset (defender) has a current market value of $87,000 (MV ). 0 Based on the used equipment market, the estimated market values at the end of the next three years are MV = $76,000, MV = $60,000, MV = $40,000. 123 The annual expenses are $18,000 in present (year-0) dollars, and these expenses are estimated to increase at 4.1% per year. The before-tax MARR is 10% per year. The best challenger available has an economic life of six years, and its EUAC over this period is $44,210. Based on this information and a before-tax analysis, when should you plan to replace the defender with the challenger?