condition mean min max ZT0-3 9.010998 9.010998 9.010998 ZT4-7 8.1717885 8.1717885 8.1717885 ZT8-11 9.539307 9.539307 9.539307 ZT12-15 9.3057105 9.3057105 9.3057105 ZT16-19 8.6539645 8.6539645 8.6539645 ZT20-23 8.804368 8.804368 8.804368