condition mean min max ZT0-3 12.694248333333334 6.545695 17.60755 ZT4-7 5.245855 5.245855 5.245855 ZT8-11 5.765885 5.765885 5.765885 ZT12-15 9.7713575 8.609815 10.9329 ZT16-19 12.0539 12.0539 12.0539 ZT20-23 20.18265 20.18265 20.18265