condition mean min max ZT0-3 380.847441 380.847441 380.847441 ZT4-7 320.41286049999997 320.41286049999997 320.41286049999997 ZT8-11 296.98116849999997 296.98116849999997 296.98116849999997 ZT12-15 337.5621645 337.5621645 337.5621645 ZT16-19 534.0917575000001 534.0917575000001 534.0917575000001 ZT20-23 665.443483 665.443483 665.443483