condition mean min max ZT0-3 6.647752499999999 5.951395 7.34411 ZT4-7 5.784385 5.784385 5.784385 ZT8-11 5.782445 5.782445 5.782445 ZT12-15 0 0 0 ZT16-19 7.246365 7.246365 7.246365 ZT20-23 7.27774 7.27774 7.27774