condition mean min max ZT0-3 2.8474583333333334 2.51971 3.13367 ZT4-7 2.398235 2.398235 2.398235 ZT8-11 2.16099 2.16099 2.16099 ZT12-15 3.4737999999999998 3.25503 3.69257 ZT16-19 3.303525 3.303525 3.303525 ZT20-23 3.305195 3.305195 3.305195