As the Steroids Era has faded away, offensive levels have returned quite close to where they were in 1992, The Year Before Everybody Got Jacked. On the surface, the two seasons look pretty similar in terms of numbers:
Stat 1992 2012 BA .256 .255 AB per game 33.93 34.00 Hits per game 8.68 8.65 Runs per game 4.12 4.32
While those basic numbers are just about mirror images, there are some massive differences as well.
For starters, league-wide slugging percentage was .377 in 1992 and .405 in 2012. The overall rate of hits is just about identical, but their distribution is different. Doubles are up about 9% and homers are up a whopping 42% while singles are down 7%. I suspect the main factor here is that pretty much all players swing for the fences now, plus those fences are a bit closer on average.
Here are some other things that have changed significantly:
Stat 1992 2012 Change Sacrifices per game 0.40 0.30 -25% TB per game 12.80 13.78 + 8% Intentional BB per gm 0.31 0.22 -40% Stolen bases per game 0.77 0.66 -14% Walks per game 3.25 3.03 - 7% Strikeouts per game 5.59 7.50 +34%
Keep in mind that these stats have all been trending–it’s not like these differences are due in large part to random noise.
So while batting average and run scoring have returned to similar levels, a lot of other things about the underlying scoring mechanisms have changed.