condition mean min max ZT0-3 4.890041666666667 2.684095 6.219865 ZT4-7 1.597025 1.597025 1.597025 ZT8-11 1.37025 1.37025 1.37025 ZT12-15 2.6038025 1.474805 3.7328 ZT16-19 4.566075 4.566075 4.566075 ZT20-23 5.742089999999999 5.742089999999999 5.742089999999999