Wall Street is reeling today upon news of December’s retail sales figures — a disappointing record that marked the biggest monthly drop in nine years.

The data, the timing of which was affected by the 35-day government shutdown, showed a decline of 1.2 percent from a month earlier to $505.8 billion. It was the steepest descent in retail sales since September 2009, when the American economy started to emerge from the Great Recession, reversing yesterday’s market gains. (The Department of Commerce, which is responsible for publishing the numbers, remained closed as President Donald Trump sparred with Democratic politicians about his proposed border wall during the shutdown.)

As of 11:30 a.m., the Dow Jones Industrial Average had dipped into the red, shedding 150 points, or nearly 0.6 percent. The S&P 500 also fell more than 0.5 percent, or almost 15 points, while the Nasdaq Composite slid 0.13 percent, or 9 points.

A critical measure of consumer spending, the weaker-than-anticipated retail sales figures suggest a dimmer outlook for the U.S. economy, which is already facing a slowdown due to December’s sharp stock market sell-off, slackening consumer confidence and trade war fears as Washington and Beijing approach a crucial tariff deadline in March.

Last week, the National Retail Federation forecasted a climb of between 3.8 and 4.4 percent in retail sales during 2019 — lowering last year’s preliminary estimate of a 4.6 percent increase. (The current forecast sees 2019 retail sales reaching $3.8 trillion.)

Investors are also wary about the global impact of China’s decelerating economic growth and whether indications of a cooling economy could help or hinder trade negotiations. If the world’s two largest economies fail to reach a deal, the White House has promised to raise tariffs from 10 percent to 25 percent on $200 billion worth of Chinese imports.

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