condition mean min max ZT0-3 6.495868333333334 4.322305 10.642700000000001 ZT4-7 5.4712250000000004 5.4712250000000004 5.4712250000000004 ZT8-11 7.5828050000000005 7.5828050000000005 7.5828050000000005 ZT12-15 5.678535 4.23649 7.12058 ZT16-19 2.463625 2.463625 2.463625 ZT20-23 4.079305 4.079305 4.079305