condition mean min max ZT0-3 139.041793 139.041793 139.041793 ZT4-7 176.24064349999998 176.24064349999998 176.24064349999998 ZT8-11 121.5860435 121.5860435 121.5860435 ZT12-15 93.4997985 93.4997985 93.4997985 ZT16-19 78.691022 78.691022 78.691022 ZT20-23 75.1255355 75.1255355 75.1255355