Baseball Reference Blog

Using the PI, we can compare how many runs are scored in a post-season game as compared to the number of runs scored in a regular-season game. It's long been my assumption that run-scoring in the post-season has been lower than the regular season since the average quality of pitching tends to be higher among playoff teams.

I don't have the time now to do the study for all years, but let's take a look at one year out of each 10, starting with 2006:

In 2006, a total of 228 runs were scored in 30 playoff games, which is an average of 3.80 runs per team per game. (That's 228 divided by 60, not by 30, since there are two teams in each game.)

Also in 2006, a total of 23599 runs were scored in 4858 regular-season games, which is an average of 4.86 runs per game. (In this case, because the data is already summing over all teams, you don't count each game twice--all 162 games for each team have already been added to the game total.)

So that gives us a baseline idea of the recent difference: 4.86 in the regular season, but just 3.80 (78%) in the post-season.

Let's look at other years in history for the same data:

Year               Regular-season R/G         Post-season R/G         % of Regular-season
1996               5.04                       4.20                      83%
1986               4.41                       4.20                      95%
1976               3.99                       4.46                     112%
1966               3.99                       1.88                      47%

So at least for this subset, there's quite a bit of variation. One thing to remember is that the 1966 data is based on just 4 post-season games (there were no league championship series back then) whereas the more recent data is based on many games.

It would be valuable to fill in all the rest of the years with the data to see what the real trends are. My guess is that these days, post-season scoring is fairly consistently around 80% of the regular-season average. (Hey OscarAzocar, this one has your name all over it.)

Related posts:

4-hit games, regular seasons vs. post-season

All Runs – Solo HRs in the Post Season

Teams With 8+ Batters With 300+ PA & 50 Or Less Runs Scored In One Season

Extra innings games vs. runs scored

Fewest career regular-season homers for a player with at least 3 post-season homers