condition mean min max ZT0-3 14.85 14.85 14.85 ZT4-7 4.9 4.9 4.9 ZT8-11 5.3 5.3 5.3 ZT12-15 7.199999999999999 7.199999999999999 7.199999999999999 ZT16-19 23.15 23.15 23.15 ZT20-23 6.8500000000000005 6.8500000000000005 6.8500000000000005