condition mean min max ZT0-3 3.15 3.15 3.15 ZT4-7 4.9 4.9 4.9 ZT8-11 12.049999999999999 12.049999999999999 12.049999999999999 ZT12-15 19.400000000000002 19.400000000000002 19.400000000000002 ZT16-19 8.299999999999999 8.299999999999999 8.299999999999999 ZT20-23 18.65 18.65 18.65