2018 was the worst for stocks in 10 years

New York(CNN Business) 2018 was a record-setting year for stocks, but it's one investors would rather forget.

The Dow fell 5.6%. The S&P 500 was down 6.2% and the Nasdaq fell 4%. It was the worst year for stocks since 2008 and only the second year the Dow and S&P 500 fell in the past decade. (The S&P 500 and Dow were down slightly in 2015, but the Nasdaq was higher that year.)

December was a particularly dreadful month: The S&P 500 was down 9% and the Dow was down 8.7% — the worst December since 1931. In one seven-day stretch, the Dow fell by 350 points or more six times. This year's Christmas Eve was the worst ever for the index.

The S&P 500 was up or down more than 1% nine times in December alone, compared to eight times in all of 2017. It moved that much 64 times during the year.

2018 wasn't all bad. The S&P 500 set an all-time record on September 20, and the Dow closed at its record on October 3. The Dow also closed more than 1,000 points higher on December 26 — the first time it ever accomplished that feat.

But 2018 will be remembered for its extreme volatility. The VIX volatility index spiked, and CNN Business' Fear & Greed Index has been stuck in "Extreme Fear" throughout much of the year. The Dow has swung 1,000 points in a single session only eight times in its history, and five of those took place in 2018.

Volatility was been driven by signs of a global economic slowdown, concerns about monetary policy, political dysfunction, inflation fears and worries about increased regulation of the technology sector.

A quiet Friday.

On Friday, the Dow rose 265 points for the day. The S&P 500 and Nasdaq each rose about 0.8%.

The market moved higher after President Donald Trump expressed optimism Saturday that the United States could strike a trade deal with China. He tweeted a deal is "moving along very well," calling negotiations "very comprehensive."

Fear of an economic slowdown, as well as a supply glut, spooked the oil market this year. US crude closed up slightly Monday but ended the year down 24.9% at $45.41 a barrel. It had closed as high as $77.41 a barrel in late June, falling 41.3% from that peak.

Stock shock is felt worldwide

Brexit's impact on the United Kingdom and Europe also worried investors, as did a slowdown in the Chinese economy.

The FTSE All-World index, which tracks thousands of stocks across a range of markets, plummeted 12% this year. It's the index's worst performance since the global financial crisis, and a sharp reversal from a gain of nearly 25% in 2017.

The market damage this year was most pronounced in China, where the world's second largest economy is feeling the effects of a darkening trade outlook and government attempts to rein in risky lending after a rapid rise in debt levels.

The Shanghai Composite entered a bear market in June and has now declined nearly 25% since the start of the year. The Shenzhen Composite, which includes many of the country's tech firms, dropped by more than 33% over the same period. In Hong Kong, the Hang Seng is down 14%.