condition mean min max ZT0-3 20.200000000000003 20.200000000000003 20.200000000000003 ZT4-7 43.4 43.4 43.4 ZT8-11 14.0 14.0 14.0 ZT12-15 12.65 12.65 12.65 ZT16-19 17.7 17.7 17.7 ZT20-23 21.85 21.85 21.85