condition mean min max ZT0-3 1.2362528092499998 0.9550628729999999 1.5174427455 ZT4-7 3.38991112375 2.0014514185 4.778370829 ZT8-11 4.285981312 4.1936606685 4.3783019555 ZT12-15 4.2999613322500005 3.7418300475 4.8580926170000005 ZT16-19 6.92864612825 6.5980493975 7.259242859 ZT20-23 7.6735935390000005 7.420611333 7.926575745