We studied the home run trends over the last four seasons in our June 30th Stat of the Week and found a four-year low. But we wondered if we were seeing the effect of the cold start of the season. Now we know the full season results.
| Year | HR/AB |
| 2005 | 3.02% |
| 2004 | 3.26% |
| 2003 | 3.12% |
| 2002 | 3.06% |
Homer Runs per At Bat (HR/AB) remained at a four-year low, though still not that much lower.
What about the percentage of runs scored by HR?
| Year | Pct of Runs Scored by HR |
| 2005 | 36.2% |
| 2004 | 37.0% |
| 2003 | 35.9% |
| 2002 | 35.8% |
Interestingly, it is the second highest of the period shown, though that might point to more emphasis on winning with power.
Maybe we need other gauges. Slugging percentage might tell us something.
| Year | Slugging |
| 2005 | 0.419 |
| 2004 | 0.428 |
| 2003 | 0.422 |
| 2002 | 0.417 |
Not a four-year low, but close.
Another gauge is isolated power (slugging percentage minus batting average).
| Year | Isolated Power |
| 2005 | 0.154 |
| 2004 | 0.162 |
| 2003 | 0.158 |
| 2002 | 0.155 |
Another four-year low, though just barely.
If you already believe the new drug testing program is causing change, you found enough statistics here to confirm your opinion. But the changes could easily be attributed to the normal random ups and downs (also called random flux) of statistics. We need to check in after next season to review the trends again, especially with the rules getting even tougher.