Oil prices continued to plummet on Wednesday while gold was enjoying its best time in six months with the release of U.S. manufacturing data for December, which appeared to show a shrinking American economy. The Institute for Supply Management Manufacturing Purchasing Manager Index (ISM PMI) came in at 48.4 in December, or 0.6% lower than November’s reading. Anything below 50 indicated contraction. The 48.4 PMI is equal to a 0.1% drop in real gross domestic product on an annualized basis, according to the ISM PMI. “Regarding…