condition mean min max ZT0-3 14.95 14.95 14.95 ZT4-7 1.3 1.3 1.3 ZT8-11 16.200000000000003 16.200000000000003 16.200000000000003 ZT12-15 21.45 21.45 21.45 ZT16-19 26.450000000000003 26.450000000000003 26.450000000000003 ZT20-23 37.599999999999994 37.599999999999994 37.599999999999994