condition mean min max ZT0-3 19.75 19.75 19.75 ZT4-7 18.0 18.0 18.0 ZT8-11 14.299999999999999 14.299999999999999 14.299999999999999 ZT12-15 4.3 4.3 4.3 ZT16-19 21.45 21.45 21.45 ZT20-23 5.0 5.0 5.0