User: Help summarize Dallas Cowboys
Assistant: The Cowboys joined the NFL as an expansion team in 1960. The team's national following might best be represented by its NFL record of consecutive sell-outs. The Cowboys' streak of 190 consecutive sold-out regular and post-season games (home and away) began in 2002. The franchise has made it to the Super Bowl eight times, tying it with the Pittsburgh Steelers and Denver Broncos for second-most Super Bowl appearances in history behind the New England Patriots' record 11 appearances. The Cowboys have won eight NFC championships, the most in the conference's history. The Cowboys are the only NFL team to record 20 straight winning seasons (from 1966 to 1985) during which they missed the playoffs only twice (1974 and 1984).

In 2015, the Dallas Cowboys became the first sports team to be valued at $4 billion, making it the most valuable sports team in the world, according to Forbes. The Cowboys also generated $620 million in revenue in 2014, a record for a U.S. sports team. In 2018, they also became the first NFL franchise to be valued at $5 billion and making Forbes' list as the most valued NFL team for the 12th straight year.