condition mean min max ZT0-3 4.315257687 3.744645321 4.885870053 ZT4-7 6.155185406999999 4.808156976499999 7.502213837499999 ZT8-11 7.436166474 6.6131681485 8.2591647995 ZT12-15 7.628981668750001 7.448641607000001 7.8093217305 ZT16-19 7.0989203765 5.573376176 8.624464577 ZT20-23 14.747915319999999 12.275448534999999 17.220382105