Last week, Monday June 29 through Sunday July 5 represented the fourth time this season scoring fell below 9.0 runs per game. At 8.8 runs per game, it was the fourth lowest week of the season. The following graph shows this year’s scoring by week against the average from 1996-2008. That the period during the high run era that there were no interruptions due to work stoppages (click for a larger image):

Note that during this period of the season, the long term trend is generally up. Warmer weather tends to lead to better hitting.

So why were the first six weeks of the season so much higher than the last seven? Teams did jettison bad veteran pitchers at that time, but it doesn’t seem like a few pitchers can make that big a difference. Some big hitters like Aramis Ramirez, Josh Hamilton and Manny Ramirez were out with injuries, but Hamilton was exactly lighting it up before he went down.

Week 20 contained Friday, May 15th, the day the Manny Ramirez suspension came down. Could that have scared players straight? I tend to doubt it, since I think it would take more time for effects to work out of the players’ systems (please correct me if I’m wrong). It’s still an interesting coincidence that since Manny suspension, all of the seven weeks since have turned in lower scoring than any of the first six weeks.