condition mean min max ZT0-3 10.237386666666666 5.77707 14.642299999999999 ZT4-7 4.3195 4.3195 4.3195 ZT8-11 5.372109999999999 5.372109999999999 5.372109999999999 ZT12-15 8.4907175 6.023585 10.95785 ZT16-19 12.309574999999999 12.309574999999999 12.309574999999999 ZT20-23 15.165849999999999 15.165849999999999 15.165849999999999