The Associated Press college basketball poll started on Jan. 20, 1949, and hasn't missed a week since. The original poll had 20 teams, with Saint Louis the first school to hold the No. 1 ranking. From the 1961-62 season through 1967-68 there was only a Top 10. It expanded again to 20 teams from 1968-69 through 1988-89. The Top 25 began the next season, and it has stayed at that number ever since. Only 12 schools have run the season at No. 1, the last being Duke in 1991-92. The record for consecutive weeks at No. 1 is 46 by UCLA from Feb. 9, 1971 through Jan. 15, 1974. Ohio State stands second in this category with a 27-week run from Dec. 1960 through March 13, 1962. UCLA has spent the most weeks at No. 1 with 134; Duke is second with 122. North Carolina, with 111, is the only other school with more than 100. The record for most schools to reach No. 1 in a season is seven in 1982-83, and the most consecutive weeks with a different No. 1 is seven in 1993-94. The AP's final poll is always released after the field for the NCAA tournament is selected. There are 23 schools that have been ranked No. 2 but have never been atop the poll. Maryland, with 23 weeks at No. 2, leads that list, which includes national champions UTEP and California. There has been a tie for No. 1 just once - Jan. 27, 1981, when Virginia and Oregon State finished as co-No. 1s.