condition mean min max ZT0-3 12.85 12.85 12.85 ZT4-7 18.9 18.9 18.9 ZT8-11 11.5 11.5 11.5 ZT12-15 23.9 23.9 23.9 ZT16-19 36.95 36.95 36.95 ZT20-23 18.450000000000003 18.450000000000003 18.450000000000003