condition mean min max ZT0-3 14.392447 14.392447 14.392447 ZT4-7 14.748032 14.748032 14.748032 ZT8-11 13.7834915 13.7834915 13.7834915 ZT12-15 12.984268 12.984268 12.984268 ZT16-19 13.5859725 13.5859725 13.5859725 ZT20-23 13.3059195 13.3059195 13.3059195