condition mean min max ZT0-3 9.8142 7.3117350000000005 11.55669 ZT4-7 6.816905 6.816905 6.816905 ZT8-11 5.084104999999999 5.084104999999999 5.084104999999999 ZT12-15 8.08829 7.550314999999999 8.626265 ZT16-19 9.773779999999999 9.773779999999999 9.773779999999999 ZT20-23 14.5862 14.5862 14.5862