condition mean min max ZT0-3 11.010239 11.010239 11.010239 ZT4-7 12.076160999999999 12.076160999999999 12.076160999999999 ZT8-11 11.1094865 11.1094865 11.1094865 ZT12-15 11.61939 11.61939 11.61939 ZT16-19 11.7205635 11.7205635 11.7205635 ZT20-23 13.180269 13.180269 13.180269