condition mean min max ZT0-3 11.311203 11.311203 11.311203 ZT4-7 12.602515 12.602515 12.602515 ZT8-11 12.173997499999999 12.173997499999999 12.173997499999999 ZT12-15 11.3952965 11.3952965 11.3952965 ZT16-19 11.0103915 11.0103915 11.0103915 ZT20-23 12.560882 12.560882 12.560882