condition mean min max ZT0-3 0.446200588 0.355482459 0.536918717 ZT4-7 1.8093206915 1.1633734665 2.4552679165 ZT8-11 5.17619484175 4.1025372065 6.249852477 ZT12-15 6.454237481250001 5.6659394370000005 7.2425355255 ZT16-19 4.54614298525 4.204938357 4.8873476135 ZT20-23 6.094469491 5.730515294 6.458423688