condition mean min max ZT0-3 4.27337 3.7589799999999998 4.7877600000000005 ZT4-7 8.186215 8.186215 8.186215 ZT8-11 11.253605 11.253605 11.253605 ZT12-15 0 0 0 ZT16-19 17.82535 17.82535 17.82535 ZT20-23 11.304965 11.304965 11.304965