condition mean min max ZT0-3 3.95063 3.95063 3.95063 ZT4-7 3.8962000000000003 3.8962000000000003 3.8962000000000003 ZT8-11 3.86376 3.86376 3.86376 ZT12-15 3.9249400000000003 3.9249400000000003 3.9249400000000003 ZT16-19 4.000243333333334 4.000243333333334 4.000243333333334 ZT20-23 4.08277 4.08277 4.08277