condition mean min max ZT0-3 131.612688 131.612688 131.612688 ZT4-7 159.9466365 159.9466365 159.9466365 ZT8-11 146.34094349999998 146.34094349999998 146.34094349999998 ZT12-15 209.99152450000003 209.99152450000003 209.99152450000003 ZT16-19 225.4619005 225.4619005 225.4619005 ZT20-23 294.983629 294.983629 294.983629