condition mean min max ZT0-3 10.598792 10.598792 10.598792 ZT4-7 9.4086585 9.4086585 9.4086585 ZT8-11 10.6356375 10.6356375 10.6356375 ZT12-15 11.503731 11.503731 11.503731 ZT16-19 10.7395105 10.7395105 10.7395105 ZT20-23 10.038632 10.038632 10.038632