condition mean min max ZT0-3 10.132677 10.132677 10.132677 ZT4-7 10.867852 10.867852 10.867852 ZT8-11 9.397195 9.397195 9.397195 ZT12-15 9.2675295 9.2675295 9.2675295 ZT16-19 9.3741565 9.3741565 9.3741565 ZT20-23 10.4430185 10.4430185 10.4430185