condition mean min max ZT0-3 3.4749499999999998 2.7766599999999997 4.17324 ZT4-7 1.2347575 1.2347575 1.2347575 ZT8-11 0.827526 0.827526 0.827526 ZT12-15 0 0 0 ZT16-19 2.641165 2.641165 2.641165 ZT20-23 2.981235 2.981235 2.981235