condition mean min max ZT0-3 16.521149 16.521149 16.521149 ZT4-7 14.9265635 14.9265635 14.9265635 ZT8-11 17.0302075 17.0302075 17.0302075 ZT12-15 18.5821325 18.5821325 18.5821325 ZT16-19 15.1595355 15.1595355 15.1595355 ZT20-23 17.967908 17.967908 17.967908