I don't know this for sure but it's more than that. I'd bet more way foul balls are hit, and still more harmlessly go into the stands, than at any point in the history of the game, because the pitchers even if they take too long between pitches and the batters have more padding and gloves to adjust between every pitch, are throwing nastier, harder to hit stuff than ever. The game's skills are testing the limits of its rules on every delivery.