Instructions: Given a passage and a query based on the passage, generate an unambiguous, concise and simple answer to the query from information in the passage. Note that the answer may not be present in exact form.
Input: 1 National Football League total attendance at regular season games 2008 to 2016 (in millions)Total attendance National Football League regular season games 2008-2016. 2 NFL average total regular season home attendance per team from 2005 to 2016Total average home attendance per team in the National Football League 2005-2016. Season and playoff development. From 1920 to 1934, the NFL did not have a set number of games for teams to play, instead setting a minimum. The league mandated a 12-game regular season for each team beginning in 1935, later shortening this to 11 games in 1937 and 10 games in 1943, mainly due to World War II. The NFL was formed in 1920 as the American Professional Football Association (APFA) before renaming itself the National Football League for the 1922 season. The NFL agreed to merge with the American Football League (AFL) in 1966, and the first Super Bowl was held at the end of that season; the merger was completed in 1970. NFL regular season games accounted for 31 out of the top 32 most-watched programs in the fall season and an NFL game ranked as the most-watched television show in all 17 weeks of the regular season. At the local level, NFL games were the highest-ranked shows in NFL markets 92% of the time. Number of people who bought clothing with logos of National Football League (NFL) teams within the last 12 months in the United States from spring 2008 to spring 2016 (in millions)People who bought clothing with NFL team logos (last 12 months) in the U.S. 2016. According to the NFL Players Association the average career length is about 3.3 years. The NFL claims that the average career is about 6 years (for players who make a club's opening day roster in their rookie season). For the 2017 season, the NFL Network will broadcast 18 regular season games under its Thursday Night Football brand, 16 Thursday-evening contests (10 of which are simulcast on either NBC or CBS) as well as one of the NFL International Series games on a Sunday morning and one of the 2017 Christmas afternoon games. 1 Number of Super Bowls won by NFL team from 1967 to 2017*National Football League: Super Bowl wins by team 2017. 2 Number of Super Bowls hosted by city from 1967 to 2017National Football League Super Bowl host cities 1967-2017. On June 24, 1922, the APFA changed its name to the National Football League (NFL). In 1932, the season ended with the Chicago Bears (616) and the Portsmouth Spartans (614) tied for first in the league standings. 1 Player salaries in the National Football League 2015/16 season (in million U.S. dollars), by team*Player salaries in the NFL 2015/16 season, by team. 2 Players with the highest salaries* in the NFL in 2016 (in million U.S. dollars)Highest paid players in the National Football League 2016. Query: how long are nfl seasons
Output:
NFL seasons take 17 weeks of the regular season.