condition mean min max ZT0-3 15.663284 15.663284 15.663284 ZT4-7 12.9639935 12.9639935 12.9639935 ZT8-11 12.3631465 12.3631465 12.3631465 ZT12-15 11.610713 11.610713 11.610713 ZT16-19 10.54345 10.54345 10.54345 ZT20-23 11.3749015 11.3749015 11.3749015