The traditional standard of 20 wins remains a high bar, with just a few pitchers getting there each season. There were three 20-game winners in 2016, two in 2015, three in 2014 and one in 2013. The peak for 20-win seasons came in the late '60s and early '70s, when many starters threw a huge number of innings. There were 15 20-game winners in 1969, 14 in 1971, 13 in 1973 (and 1951) and 11 in 1970 and 1974. As the five-man rotation became standard by the 1980s, the 40-game starter became obsolete. Then the complete game neared extinction.
The early years of the NL were tumultuous, with threats from rival leagues and a rebellion by players against the hated "reserve clause", which restricted the free movement of players between clubs. Competitor leagues formed regularly and also disbanded regularly. The most successful was the American Association (1882–1891), sometimes called the "beer and whiskey league" for its tolerance of the sale of alcoholic beverages to spectators. For several years, the NL and American Association champions met in a postseason championship series—the first attempt at a World Series . The two leagues merged in 1892 as a single 12-team NL, but the NL dropped four teams after the 1899 season. This led to the formation of the American League in 1901 under AL president Ban Johnson , and the resulting bidding war for players led to widespread contract-breaking and legal disputes.