condition mean min max ZT0-3 11.600000000000001 11.600000000000001 11.600000000000001 ZT4-7 4.9 4.9 4.9 ZT8-11 7.6 7.6 7.6 ZT12-15 20.799999999999997 20.799999999999997 20.799999999999997 ZT16-19 16.25 16.25 16.25 ZT20-23 25.8 25.8 25.8