condition mean min max ZT0-3 1.98937343325 1.5066775605 2.472069306 ZT4-7 1.7619136499999999 1.089136671 2.434690629 ZT8-11 6.32858703875 4.5686939265 8.088480151 ZT12-15 6.2828801195 5.8471465625 6.7186136765 ZT16-19 4.449462757 4.211908913 4.687016601 ZT20-23 8.28853085 6.834829706 9.742231994