“It’s a red flag, and you need to be cognizant of what’s driving it,” Sean Simko, head of global fixed-income management at SEI Investments, told the WSJ.

Long-term Treasury yields are also being depressed by an increased demand out of U.S. pension funds as companies take advantage of temporary tax savings, report Ben Eisen and Daniel Kruger for the WSJ.

S&P 500 companies are contributing to pension plans this year at a pace expected to match 2017 levels at $63 billion, the most since 2003, according to Goldman Sachs Asset Management. pension funds also tend to invest in long-dated bonds to match their long-term liabilities, which has contributed to a rise in long-term bonds or falling yields.

Long-term yields are “very low because people are still putting money into Treasurys,” Torsten Slok, an economist at Deutsche Bank, told the WSJ.

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