condition mean min max ZT0-3 3.6005000000000003 3.6005000000000003 3.6005000000000003 ZT4-7 3.121555 3.121555 3.121555 ZT8-11 3.0077350000000003 3.0077350000000003 3.0077350000000003 ZT12-15 2.748665 2.748665 2.748665 ZT16-19 4.35691 4.35691 4.35691 ZT20-23 3.5905 3.5905 3.5905