condition mean min max ZT0-3 237.456706 237.456706 237.456706 ZT4-7 261.158832 261.158832 261.158832 ZT8-11 199.38246 199.38246 199.38246 ZT12-15 232.690792 232.690792 232.690792 ZT16-19 174.298499 174.298499 174.298499 ZT20-23 188.65412800000001 188.65412800000001 188.65412800000001