condition mean min max ZT0-3 7.44104321925 6.088050189 8.7940362495 ZT4-7 5.4421792377500005 4.1014947905 6.782863685 ZT8-11 3.3458313750000004 3.0131772310000002 3.678485519 ZT12-15 17.60177183725 15.0280424595 20.175501214999997 ZT16-19 27.26648337 25.95033102 28.58263572 ZT20-23 24.5831034775 23.82306421 25.343142745