condition mean min max ZT0-3 12.379624999999999 12.143149999999999 12.6161 ZT4-7 6.091665 6.091665 6.091665 ZT8-11 6.505554999999999 6.505554999999999 6.505554999999999 ZT12-15 0 0 0 ZT16-19 10.70785 10.70785 10.70785 ZT20-23 8.893895 8.893895 8.893895