condition mean min max ZT0-3 6.1997875 6.19448 6.205095 ZT4-7 5.270015000000001 5.270015000000001 5.270015000000001 ZT8-11 9.389625 9.389625 9.389625 ZT12-15 0 0 0 ZT16-19 9.151125 9.151125 9.151125 ZT20-23 7.723879999999999 7.723879999999999 7.723879999999999