Black Friday. Small Business Saturday. Cyber Monday. These three shopping events are designed to attract shoppers and pump up retail sales high enough to keep some businesses afloat the rest of the year.

These three days are said to mean the difference between a boon or bust year for retailers. But how much of this is hype? How important are these shopping events to retailers and the national economy?

The U.S. Census Bureau’s data offer some key insight. “These three shopping days really do play a big role in kicking off the holiday shopping season and helping the economy as a whole,” said Andrew Hait, a statistician in the International Trade Management Division. “The Census Bureau is able to measure the economic impact of the holiday shopping season in several ways.”

The Monthly Retail Trade Survey showed that 8.5 percent of the approximately $5.5 trillion in total retail and food services sales during 2016 was generated during November and 9.8 percent was generated in December.

November and December are big-money months for the retail and food services industries. The Monthly Retail Trade Survey showed that 8.5 percent of the approximately $5.5 trillion in total retail and food services sales during 2016 was generated during November and 9.8 percent was generated in December. (These monthly sales estimates are not adjusted for seasonal variation, or holiday or trading day differences.)

November and December are even more important for certain industries. Of the nearly $18.8 billion in sales from hobby, toy and game stores in 2016, 12.3 percent was in November and 18.9 percent was in December.

Of the total sales from department stores (excluding discount department stores) in 2016 ($56.4 billion), 10.3 percent were in November and 15.7 percent were in December. Finally, nearly 19.8 percent of 2016’s annual sales from jewelry stores ($32.9 billion) was earned in December alone.

Online sales are increasingly important. According to the Census Bureau’s Quarterly E-Commerce report, $122.5 billion of the $1.3 trillion in total retail sales (or 9.4 percent) were attributed to e-commerce in fourth quarter 2016. This was up 32.2 percent from the e-commerce sales reported in third quarter 2016, $92.6 billion, or 7.6 percent of total retail sales.

And there’s nothing small about the role of small businesses. The Statistics of U.S. Businesses program reports about 5.3 million of the total 5.9 million employer firms in the United States in 2015 had fewer than 20 employees.

These small businesses employed 20.8 million people and reported total annual payrolls of $828.7 billion. While enterprises with more than 500 employees reported total employment of 65.1 million, there are only 19,464 of these large firms.

“Large retail businesses anchor local shopping centers, but dozens of small retail businesses often make up the character of the shopping center and bring in a lot of money,” Hait said. “For many retail trade businesses, a successful holiday shopping season can make the difference between staying in business and closing their doors.”

There’s no question that a healthy holiday shopping season matters to retailers and our economy as a whole. Whether you shop Black Friday, Small Business Saturday or Cyber Monday, retailers hope that ‘tis the season for holiday sales.

Julie Iriondo is a public affairs specialist at the U.S. Census Bureau.