condition mean min max ZT0-3 2.3642016666666668 1.95267 3.144725 ZT4-7 1.78721 1.78721 1.78721 ZT8-11 2.33964 2.33964 2.33964 ZT12-15 5.4193175 5.047510000000001 5.791125 ZT16-19 4.56693 4.56693 4.56693 ZT20-23 4.207035 4.207035 4.207035