condition mean min max ZT0-3 11.851911666666666 9.552435 13.060500000000001 ZT4-7 5.5729500000000005 5.5729500000000005 5.5729500000000005 ZT8-11 5.005955 5.005955 5.005955 ZT12-15 6.6140425 4.981205 8.24688 ZT16-19 7.27622 7.27622 7.27622 ZT20-23 12.2333 12.2333 12.2333