MLB players suddenly started hitting more home runs in 2015 and they haven't slowed down since

Through about one-fifth of the Major League Baseballseason, the players are on pace to hit 5,730 home runs, which would break the record of5,693 home runs hit during the 2000 season in the heart of the so-called "steroid era." What is interesting about this surge is that something seemingly changed, either prior to, or during the 2015 season. That's when the fly balls suddenly started flying out of ballparks more often. During the first half of the 2015 season, 10.7% of all fly balls went over t...