condition mean min max ZT0-3 9.138912 9.138912 9.138912 ZT4-7 9.037425 9.037425 9.037425 ZT8-11 9.0018905 9.0018905 9.0018905 ZT12-15 9.720894 9.720894 9.720894 ZT16-19 8.590308499999999 8.590308499999999 8.590308499999999 ZT20-23 8.734113 8.734113 8.734113