Television has also altered how sports leagues run. To reach additional TV markets, all of the main professional sports have increased the number of teams. The National Hockey League (NHL), for example, has expanded from six to thirty clubs. This allows more games to be televised and increases revenue sharing with its clubs. Another effect of television is that sports now play a major role in attracting viewers to networks. Sports provide much needed drama and action that can help make up for poor programming on other days. Baseball and football alone account for almost half of all network entertainment advertising. In fact, during NFL season, you can be sure that many people will watch TV just to see what game will be played that day. Finally, sports have become a major part of society's culture. Everyone from little kids to seniors watch sports games. And they all have their own opinion about who will win or lose. As sports become more popular, we can expect to see more changes keep coming our way.