condition mean min max ZT0-3 17.85 17.85 17.85 ZT4-7 4.8 4.8 4.8 ZT8-11 23.049999999999997 23.049999999999997 23.049999999999997 ZT12-15 23.9 23.9 23.9 ZT16-19 9.55 9.55 9.55 ZT20-23 7.3500000000000005 7.3500000000000005 7.3500000000000005