Goldman Sachs said on Friday that it expects fourth-quarter earnings to decrease by about five billion dollars, due to the new U.S. tax law signed by President Donald Trump last week. However, the impact of the tax legislation may differ from the estimate. The new law significantly lowers the income tax rate for U.S. companies, to 21 percent from 35 percent. That allows them to repatriate cash from overseas, and modifies numerous deductions, among other changes.