Size depends on who you ask, as it varies a bit. Generally it seems the most accepted model around here is major market (1-20), large market (21-50), medium market (51-100), and small market (101+). However, RadioInk, which has a lot of clout, says it's major market (1-10), large market (11-30), medium market (31-100), and small market (101+). When Clear Channel decided to sell off small markets, they considered small markets to be about 111+. (Nashville, of course, is #44.)