condition mean min max ZT0-3 14.8473 10.45725 17.91395 ZT4-7 6.0700400000000005 6.0700400000000005 6.0700400000000005 ZT8-11 7.409844999999999 7.409844999999999 7.409844999999999 ZT12-15 13.91278 10.21771 17.60785 ZT16-19 14.2352 14.2352 14.2352 ZT20-23 17.16895 17.16895 17.16895