condition mean min max ZT0-3 4.45 4.45 4.45 ZT4-7 31.7 31.7 31.7 ZT8-11 11.2 11.2 11.2 ZT12-15 2.9000000000000004 2.9000000000000004 2.9000000000000004 ZT16-19 21.0 21.0 21.0 ZT20-23 14.049999999999999 14.049999999999999 14.049999999999999