Originally, the game took place in early to mid-January. For Super Bowl I there was only one round of playoffs: the pre-merger NFL and AFL Championship Games. The addition of two playoff rounds (first in 1967 and then in 1978), an increase in regular season games from 14 to 16 (1978), and the establishment of one bye-week per team (1990) have caused the Super Bowl to be played later. Partially offsetting these season-lengthening effects, simultaneous with the addition of two regular season games in 1978, the season was started earlier. Prior to 1978 the season started as late as September 21. Now, since Labor Day is always the first Monday of September, September 13 is the latest possible date for the first full Sunday set of games (Since 2002, the regular season has started with the Kickoff Game on the Thursday after Labor Day).