condition mean min max ZT0-3 15.99575 15.99575 15.99575 ZT4-7 17.13865 17.13865 17.13865 ZT8-11 13.1915 13.1915 13.1915 ZT12-15 10.6517 10.6517 10.6517 ZT16-19 11.8486 11.8486 11.8486 ZT20-23 12.65835 12.65835 12.65835