condition mean min max ZT0-3 20.7208 18.9892 22.4524 ZT4-7 11.3174 11.3174 11.3174 ZT8-11 9.266425000000002 9.266425000000002 9.266425000000002 ZT12-15 0 0 0 ZT16-19 20.1987 20.1987 20.1987 ZT20-23 21.48075 21.48075 21.48075