condition mean min max ZT0-3 161.376246 161.376246 161.376246 ZT4-7 190.4594235 190.4594235 190.4594235 ZT8-11 222.66572050000002 222.66572050000002 222.66572050000002 ZT12-15 228.31316099999998 228.31316099999998 228.31316099999998 ZT16-19 277.84752849999995 277.84752849999995 277.84752849999995 ZT20-23 262.727107 262.727107 262.727107