Richard and Fiona Simon (plaintiffs) were professional violin players for the New York Philharmonic Orchestra. In 1985, both Richard and Fiona purchased a violin bow made by Francois Tourte. Tourte was considered the premiere violin bow maker, and each bow was made in the nineteenth century. Older violins and older bows produced better sound than newer counterparts, and frequent use of a violin bow deteriorated the quality of sound produced by a violin. When Richard and Fiona bought the Tourte violin bows, the bows were relatively unused. By the time of trial, both bows had noticeably deteriorated. Although each bow had deteriorated with respect to sound quality, each bow had also increased in fair market value as an antique. The Simons deducted an amount for depreciation of recovery property on their 1989 tax return, based on the accelerated cost recovery system (ACRS). The commissioner of internal revenue (commissioner) (defendant) issued a notice of deficiency against the Simons as a result. The Simons petitioned the United States Tax Court for a redetermination.