condition mean min max ZT0-3 11.258495236 9.495581882 13.02140859 ZT4-7 8.450618148500002 8.304253861000001 8.596982436000001 ZT8-11 11.758637353 9.7765184955 13.740756210499999 ZT12-15 17.365452175 15.862575575 18.868328775000002 ZT16-19 16.5526598075 16.37965983 16.725659784999998 ZT20-23 16.068983635000002 15.380433570000001 16.7575337