Five years ago, Thomas Martin installed production machinery that had a first cost of $25,000. At that time initial yearly costs were estimated at $1,250, increasing by $500 each year. The market value of this machinery each year would be 90% of the previous year's value. There is a new machine available now that has a first cost of $27,900 and no yearly costs over its five-year minimum cost life. If Thomas Martin uses an 8% before-tax MARR, when, if at all, should he replace the existing machinery with the new unit