condition mean min max ZT0-3 6.88299 6.88299 6.88299 ZT4-7 7.111619999999999 7.111619999999999 7.111619999999999 ZT8-11 4.2623549999999994 4.2623549999999994 4.2623549999999994 ZT12-15 1.451525 1.451525 1.451525 ZT16-19 3.293515 3.293515 3.293515 ZT20-23 6.996475 6.996475 6.996475