condition mean min max ZT0-3 5.25 5.25 5.25 ZT4-7 5.7 5.7 5.7 ZT8-11 17.5 17.5 17.5 ZT12-15 9.049999999999999 9.049999999999999 9.049999999999999 ZT16-19 5.65 5.65 5.65 ZT20-23 3.9 3.9 3.9