condition mean min max ZT0-3 10.734571 10.734571 10.734571 ZT4-7 11.9759815 11.9759815 11.9759815 ZT8-11 11.2925505 11.2925505 11.2925505 ZT12-15 13.1925045 13.1925045 13.1925045 ZT16-19 10.8917575 10.8917575 10.8917575 ZT20-23 11.4593635 11.4593635 11.4593635