condition mean min max ZT0-3 9.85366 9.85366 9.85366 ZT4-7 15.00925 15.00925 15.00925 ZT8-11 6.320235 6.320235 6.320235 ZT12-15 3.928555 3.928555 3.928555 ZT16-19 2.7238749999999996 2.7238749999999996 2.7238749999999996 ZT20-23 5.685345 5.685345 5.685345