condition mean min max ZT0-3 6.300000000000001 6.300000000000001 6.300000000000001 ZT4-7 3.1 3.1 3.1 ZT8-11 15.35 15.35 15.35 ZT12-15 2.95 2.95 2.95 ZT16-19 17.45 17.45 17.45 ZT20-23 13.75 13.75 13.75