condition mean min max ZT0-3 1.5318136666666666 1.5318136666666666 1.5318136666666666 ZT4-7 1.52915 1.52915 1.52915 ZT8-11 0.633423 0.633423 0.633423 ZT12-15 0.952366 0.952366 0.952366 ZT16-19 2.6367499999999997 2.6367499999999997 2.6367499999999997 ZT20-23 1.84329 1.84329 1.84329