condition mean min max ZT0-3 21.3 21.3 21.3 ZT4-7 31.5 31.5 31.5 ZT8-11 14.049999999999999 14.049999999999999 14.049999999999999 ZT12-15 18.6 18.6 18.6 ZT16-19 7.6 7.6 7.6 ZT20-23 9.3 9.3 9.3