Slow Starts

Game 4 of the 2016 World Chess Championship ran a similar course to game 3. Carlsen gained an advantage, tried to grind down Karjakin, missed stronger moves in the ending, and the game was a draw.  So 4 games, 4 draws to start the match.
This got me thinking about previous matches, and how long fans had to wait to see a decisive result. At first I thought that the move to a 12 game format (which I dislike) caused players to start more cautiously, but it turns out that this isn't always the case, and I was only remembering the worst cases.
Going backwards (until 2000) here is a list of matches with the game number of the first decisive game, as well as if it was won by the eventual match winner or loser.

• 2014 2 (W)
• 2013 5 (W)
• 2012 7 (L)
• 2010 1 (L)
• 2008 3 (W)
• 2004 1 (W) (14 games)
• 2000 2 (W) (16 games)

At a stretch I would argue that the starts are getting slower in recent matches. It also helps to be the first to take the lead, although Anand came from behind in both 2010 and 2012 (but not in 2013 or 14).