condition mean min max ZT0-3 1.9500000000000002 1.9500000000000002 1.9500000000000002 ZT4-7 2.2 2.2 2.2 ZT8-11 3.25 3.25 3.25 ZT12-15 11.1 11.1 11.1 ZT16-19 3.15 3.15 3.15 ZT20-23 1.25 1.25 1.25