been posited to account for the dramatic increase in home runs at the new Yankee Stadium over the original stadium, foremost among these the sharper angles of the outfield walls and the speculated presence of a wind tunnel. During construction of the new ballpark, engineers commissioned a wind study, the results of which indicated there would be no noticeable difference between the two stadiums. The franchise planned a second study, but Major League rules prohibit a team from making any changes to the playing field until the off-season. An independent study by the weather service provider AccuWeather in June 2009 concluded that the shape and height of the right field wall, rather than the wind, is responsible for the proliferation of home runs at the stadium. AccuWeather's analysis found that roughly 20% of the home runs hit at the new ballpark would not have been home runs at the old ballpark due to the gentle curve of its right field corner, and its wall height. Nothing was observed in wind speeds and patterns that would account for the increase. The number of home runs hit at the new stadium slowed significantly as the season progressed, but a new single-season record for most home runs hit at a Yankee home ballpark was nonetheless set in the Yankees' 73rd home game of 2009 when Vladimir Guerrero of the Los Angeles Angels of Anaheim hit the 216th home run of the season at the venue, surpassing the previous record of 215 set at the original Yankee Stadium in 2005. However, the Yankees offense, as in previous years, had employed many home run hitters in 2009. The Yankees hit 108 home runs while playing on the road, the second most in baseball behind the Philadelphia Phillies. In 2010, the early rate of home runs were markedly less through May 15, 2010, with 35 home runs hit in 14 games for 2.5 per game (a projection of 205—in 2009, the stadium finished at 2.93 per game for a total of 237). Even though the stadium's home run rate decreased slightly for the 2010 season to 2.73 per game, it was still the highest figure in the majors. However, the prolific home run rate of April and May 2009 that drew criticism has not sustained itself over any season thus far, and while through the first two months of the 2011 season the Yankees hit far