condition mean min max ZT0-3 2.218285 2.218285 2.218285 ZT4-7 1.00491 1.00491 1.00491 ZT8-11 1.021874 1.021874 1.021874 ZT12-15 1.475345 1.475345 1.475345 ZT16-19 1.4369045 1.4369045 1.4369045 ZT20-23 2.0504000000000002 2.0504000000000002 2.0504000000000002