New York (CNN Business) President Donald Trump signed sweeping tax cuts into law one year ago. That boosted the stock market and the economy in early 2018, but the initial rush of excitement is fading fast.

The Dow and S&P 500 have each fallen nearly 8% since December 22, 2017 — the day Trump put his name on the Tax Cuts and Jobs Bill Act.

The euphoric reaction to the wave of big stock buybacks and increased dividends from Corporate America has now been replaced by concerns about trade tension with China, worries that the Federal Reserve has gone too far with its rate hikes and the likelihood that earnings growth will slow dramatically in 2019.

The broader economy has held up better. Gross domestic product rose at a 4.2% annualized pace in the second quarter of 2017 and grew 3.4% in the third quarter.

However, the Fed is expecting that GDP will rise at only a 2.3% clip next year. Jobs growth has begun to slow as well, which is another troubling sign. Some on Wall Street worry that a recession could come as soon as 2020.

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