condition mean min max ZT0-3 13.398583333333333 11.7371 15.298649999999999 ZT4-7 9.955504999999999 9.955504999999999 9.955504999999999 ZT8-11 9.552254999999999 9.552254999999999 9.552254999999999 ZT12-15 12.14345 11.1245 13.1624 ZT16-19 12.14735 12.14735 12.14735 ZT20-23 11.94985 11.94985 11.94985