Baseball-Reference.com has a handy page (HT to JC Bradbury) where they are tracking changes in MLB team attendance. It calculates overall attendance, per-game attendance, and comparisons between this year and last year. It also allows you to sort the data and it allows you to display the data in csv format for copying and pasting into your favorite spreadsheet.
As of yesterday (May 15th, 2009), teams as a whole have seen per-game attendance drop by about 5%. While the Yankees, as usual, are garnering most of the headlines (especially with their $2,500 dollar a game seats), the Mets, Nationals, and Tigers all have seen steeper declines in average attendance.
Nine teams have realized attendance increases with the Tampa Bay Rays leading the way. That's not at all surprising given their success on the field last year. Studies routinely show that when teams perform well one year, their attendance tends to be higher the following year because the good performance changes fan expectations, ceteris paribus.
The recession is surely hurting teams. Both the Mets and the Yankees have moved into new palaces, which should ceteris paribus translate into attendance increases, but both rank in the top 4 in per-game attendance decreases with the Mets seeing the sharpest decline so far.
As I metioned above, a lot of attention has been given to the pricing policies of the Yankees. It certainly is possible that they erred when setting ticket prices, but without digging deeper into the numbers, it's hard to say how much of the decline is due to factors such as weather, the recession, poor pricing policies, team quality, changes in capacity, etc. The Yankees' new ballpark has a capacity of 51,800 while the old Yankee stadium had a capacity of 57,545. The Mets' new ballpark has a capacity of 45,000 while its old ballpark had a capacity of 55,601. Surely this is one of the factors that explains why fewer fans are attending Yanks and Mets games this year.
Cross-posted at Market Power.