condition mean min max ZT0-3 5.541475 5.541475 5.541475 ZT4-7 2.859375 2.859375 2.859375 ZT8-11 1.6465800000000002 1.6465800000000002 1.6465800000000002 ZT12-15 3.9364100000000004 3.9364100000000004 3.9364100000000004 ZT16-19 14.532265 14.532265 14.532265 ZT20-23 9.238335 9.238335 9.238335