This past week was a wild one for the stock market.

Each of the major U.S. averages lost more than 5% with the Dow losing more than 1,000 points in a single day twice. Despite a more than 1% rally to cap the week on Friday, each of the Dow, S&P 500, and Nasdaq lost 5.2%. It was the worst week since January 2016.

Monday’s sell-off, which was the largest point decline in the Dow’s history as the blue chip index shed 1,175 points, was chaotic and disorienting. And by week’s end, both investors and those not steeped in financial markets were left asking the same question — what just happened?

It all starts with the January jobs report

Perhaps the most frustrating part of this week’s action is that unlike declines around the debt ceiling in 2011, or concerns over the Chinese economy in 2015, or post-Brexit and post-election market sell-offs seen in 2016, there was no one thing you could point to and say, “This is what made markets go down.”

A number of factors were at play in markets this week, some of which seem more potent than others, and all of which contributed to the hectic trading. But the chaos seen this past week really begins the week before last.

View photos It was a historic week for the Dow as the blue-chip index lost more than 1,000 points in a single day twice. Monday’s 1,175-point slide was its largest ever. (Source: Yahoo Finance) More

On Friday, February 2, the January jobs report was released and showed that more jobs were added to the economy than expected during the first month of the year while wage growth was also stronger than expected.

Coming at the end of a week that saw Treasury yields continue to move to multi-year highs, strong wage data was seen by many as confirming bond market fears that inflation is coming to the U.S. economy this year.

In turn, markets started to believe the Federal Reserve would have to be more aggressive in raising interest rates in 2018 and beyond. The increase in interest rates that had been seen since the start of 2018, all at once, became a primary concern for the stock market. Stocks sold off hard into the weekend. (Notably, interest rates stayed elevated during this week’s market sell-off, indicating no fundamental re-rating of how investors see the economic playing field — wage growth, inflation, and a more aggressive Fed are still baked in.)

The post-jobs-report market stress continued into Monday. And this is when the “higher rates” trade became the “higher volatility” trade.

The VIX index, which tracks current and expected market volatility, spiked higher as the week’s first trading day drew to an end. In 2017, the VIX hit a record low of 8.64. By Monday afternoon the index was at 50. This surge in volatility — both realized and expected — led to the implosion of an exchange-traded fund designed to help investors bet against volatility. One of the trendiest trades of 2017 was reversed almost overnight.

View photos Strong news about American workers in January sowed the seeds of investor anxiety in February. (AP Photo/Keith Srakocic) More

When trading closed on Monday, the stock market was down about 4% with the Dow falling 1,175 points and Treasuries did not prove to be the safe haven many expect them to be in a market storm. With this kind of market action breaking out, it became clear that worries over inflation were a weak excuse for a wholesale panic in markets. Something else was going on.

And concerns over a Credit Suisse-sponsored fund — the VelocityShares Daily Inverse VIX Short Term exchange-traded note, which trades under the ticker XIV — and the broader volatility in markets impacted shares of Credit Suisse (CS), which fell 8% this week, as well as the Cboe (CBOE), which houses the VIX index. Shares of Cboe lost over 20% this week.