condition mean min max ZT0-3 4.158883333333334 1.218105 6.758915 ZT4-7 0.0 0.0 0.0 ZT8-11 0.0 0.0 0.0 ZT12-15 1.736235 1.23848 2.23399 ZT16-19 2.1250400000000003 2.1250400000000003 2.1250400000000003 ZT20-23 1.220345 1.220345 1.220345