condition mean min max ZT0-3 8.651728333333333 6.747615 10.469850000000001 ZT4-7 19.7774 19.7774 19.7774 ZT8-11 13.927 13.927 13.927 ZT12-15 6.5879575 5.64806 7.527855 ZT16-19 8.758505 8.758505 8.758505 ZT20-23 8.210795000000001 8.210795000000001 8.210795000000001