condition mean min max ZT0-3 1.7645878333333334 1.1796025 2.663525 ZT4-7 2.30229 2.30229 2.30229 ZT8-11 0.589095 0.589095 0.589095 ZT12-15 2.77156 1.51336 4.02976 ZT16-19 0.5596805 0.5596805 0.5596805 ZT20-23 2.8468400000000003 2.8468400000000003 2.8468400000000003