condition mean min max ZT0-3 251.045782 251.045782 251.045782 ZT4-7 381.49873149999996 381.49873149999996 381.49873149999996 ZT8-11 339.688293 339.688293 339.688293 ZT12-15 362.54573849999997 362.54573849999997 362.54573849999997 ZT16-19 304.40457200000003 304.40457200000003 304.40457200000003 ZT20-23 203.0317945 203.0317945 203.0317945