condition mean min max ZT0-3 1131.6 1131.6 1131.6 ZT4-7 1375.7 1375.7 1375.7 ZT8-11 1582.2 1582.2 1582.2 ZT12-15 1870.5 1870.5 1870.5 ZT16-19 1498.1999999999998 1498.1999999999998 1498.1999999999998 ZT20-23 1085.95 1085.95 1085.95