condition mean min max ZT0-3 8.988711666666667 7.74967 9.772655 ZT4-7 8.895795 8.895795 8.895795 ZT8-11 5.602595 5.602595 5.602595 ZT12-15 6.6227075 4.6854 8.560015 ZT16-19 6.64801 6.64801 6.64801 ZT20-23 9.67592 9.67592 9.67592