It's by percentage

Benjamin Hill over at milb.com has a column on teams with the largest percentage increases in attendance over the last three seasons.

There are two teams on the list from 2008 (edit: added in for clarity) and one of them is from right here in the Midwest League.

6. Quad Cities River Bandits, 2008
Average attendance: 3,451 (53% increase over the previous season)

Under the leadership of new owner Dave Heller and GM Kirk Goodman, the River Bandits implemented a staggering array of changes in 2008. After four years as the awkwardly named "Swing of the Quad Cities," the club returned to the River Bandits moniker and unveiled a new logo. Meanwhile, a much greater emphasis was put on the game-day experience at Modern Woodman (formerly John O'Donnell) Park. In addition to a greatly expanded concession stand menu, fans were able to enjoy a drink at the Tiki Lounge and even take a dip in the hot tub overlooking right field.

That's great and all, but the windows in the press box still don't open.