condition mean min max ZT0-3 16.52885 16.52885 16.52885 ZT4-7 11.86505 11.86505 11.86505 ZT8-11 12.07775 12.07775 12.07775 ZT12-15 14.53595 14.53595 14.53595 ZT16-19 29.55075 29.55075 29.55075 ZT20-23 19.7009 19.7009 19.7009