condition mean min max ZT0-3 6.9 6.9 6.9 ZT4-7 4.9 4.9 4.9 ZT8-11 5.699999999999999 5.699999999999999 5.699999999999999 ZT12-15 7.45 7.45 7.45 ZT16-19 6.199999999999999 6.199999999999999 6.199999999999999 ZT20-23 14.600000000000001 14.600000000000001 14.600000000000001