condition mean min max ZT0-3 33.416246 33.416246 33.416246 ZT4-7 27.467754 27.467754 27.467754 ZT8-11 30.819961499999998 30.819961499999998 30.819961499999998 ZT12-15 34.075281000000004 34.075281000000004 34.075281000000004 ZT16-19 37.050833999999995 37.050833999999995 37.050833999999995 ZT20-23 31.694580000000002 31.694580000000002 31.694580000000002