condition mean min max ZT0-3 13.75 13.75 13.75 ZT4-7 9.3 9.3 9.3 ZT8-11 17.55 17.55 17.55 ZT12-15 12.95 12.95 12.95 ZT16-19 13.45 13.45 13.45 ZT20-23 12.850000000000001 12.850000000000001 12.850000000000001