condition mean min max ZT0-3 10.21653 10.21653 10.21653 ZT4-7 9.665687 9.665687 9.665687 ZT8-11 10.3666305 10.3666305 10.3666305 ZT12-15 9.494752 9.494752 9.494752 ZT16-19 8.8189925 8.8189925 8.8189925 ZT20-23 9.45763 9.45763 9.45763