condition mean min max ZT0-3 18.1968 15.799949999999999 20.59365 ZT4-7 10.37706 10.37706 10.37706 ZT8-11 9.771840000000001 9.771840000000001 9.771840000000001 ZT12-15 0 0 0 ZT16-19 10.303975 10.303975 10.303975 ZT20-23 12.63665 12.63665 12.63665