condition mean min max ZT0-3 414.217823 414.217823 414.217823 ZT4-7 353.40387 353.40387 353.40387 ZT8-11 431.50183549999997 431.50183549999997 431.50183549999997 ZT12-15 451.2995055 451.2995055 451.2995055 ZT16-19 506.1462815 506.1462815 506.1462815 ZT20-23 466.6370455 466.6370455 466.6370455