condition mean min max ZT0-3 16.506513 16.506513 16.506513 ZT4-7 25.568811500000002 25.568811500000002 25.568811500000002 ZT8-11 25.886737500000002 25.886737500000002 25.886737500000002 ZT12-15 21.276137 21.276137 21.276137 ZT16-19 17.8667665 17.8667665 17.8667665 ZT20-23 18.56701 18.56701 18.56701