condition mean min max ZT0-3 6.71018 6.71018 6.71018 ZT4-7 5.589605000000001 5.589605000000001 5.589605000000001 ZT8-11 4.89119 4.89119 4.89119 ZT12-15 6.203475 6.203475 6.203475 ZT16-19 7.764060000000001 7.764060000000001 7.764060000000001 ZT20-23 5.875005 5.875005 5.875005