Love it or hate it, marijuana has been a hot topic in the U.S. and Canada over the last couple of years. Twenty-nine U.S. states plus the District of Columbia now allow legal use of medical marijuana, with eight states plus D.C. permitting recreational use of the drug. All of Canada allows legal use of medical marijuana -- and efforts are underway to make recreational use legal across the country.

But as much talk as there's been about marijuana, there are still plenty of things that many people might not realize about the status of public perception and actual use of the drug. Here are 10 marijuana statistics that will blow you away.

1. 55 million Americans used marijuana in the past year

This number comes from a survey conducted by Altaba's Yahoo News and Marist College. It includes roughly 35 million adults who use marijuana at least once or twice per month and another 20 million who have used marijuana once or twice in the past year.

2. 129 million American adults have tried marijuana

A recent Gallup poll found that 45% of Americans have tried marijuana at least once. However, the Yahoo News/Marist College survey reported that 52% of American adults have tried the drug at some point in their lives. That translates to around 129 million people.

3. 83% of Americans support legalizing medical marijuana

You might have seen some polls showing that a solid majority of Americans support legalization of marijuana. The really strong support, though, is for legalization of medical marijuana. The Yahoo News/Marist College survey reported that 83% of respondents supported legalization of medical marijuana. That's consistent with another survey conducted by Quinnipiac University.

4. 13,000 kilowatts/hour of electricity used to produce 5 pounds of marijuana

Evan Mills from the Lawrence Berkeley National Laboratory in California did an analysis and calculated how much electricity was used in California's greenhouses in the production of marijuana. To put his 13,000 kilowatts figure into perspective, it's more electricity than the average U.S. household uses in a year.

5. 60 million gallons of water per day used in California's marijuana growing season

It takes a lot of water to grow marijuana. How much is 60 million gallons per day? It's 50% more than every person living in San Francisco uses.

6. At least 165,000 cannabis industry workers in U.S.

Marijuana Business Daily, a publication focusing on the medical marijuana and retail cannabis industry, estimates that between 165,000 and 230,000 people work in the U.S. cannabis industry. This estimate includes employment data for retailers, wholesaler, testing labs, and ancillary companies. If the midpoint of this range is used, it means that there are more cannabis industry workers than there are dental hygienists in the U.S.

7. Around 25% fewer opioid-related deaths in states with legal medical marijuana

The opioid epidemic is a huge problem in the U.S. However, research has found that the annual rate of deaths due to opioid overdoses was nearly 25% lower in states that allow legal use of medical marijuana. Some clinical studies indicate that medical marijuana could be effective in helping to alleviate pain.

8. $655 million in tax revenue from marijuana estimated for 2017

States where marijuana is legal could generate tax revenue from marijuana totaling $655 million, according to projections by New Frontier Data. Much of this figure stems from states with legalized medical marijuana. However, politicians in states such as New Jersey are also seriously eyeing the potential to boost tax revenue from recreational marijuana.

9. $6.7 billion sales for marijuana in North America last year

Arcview Market Research estimates that the North American market for marijuana in 2016 totaled $6.7 billion. And that's 30% higher than the previous year. Arcview compares the growth in the marijuana industry to the growth of cable television in the 1990s and broadband internet in the first decade of the 21st century.

10. $37.3 billion U.S. marijuana market by 2024

How big could the U.S. marijuana market grow? According to data from Statista, within seven years it could hit $37.3 billion, including both medical and recreational marijuana markets. And this doesn't include the Canadian marijuana market, which professional services firm Deloitte thinks could generate $8.7 billion annually if efforts to legalize recreational marijuana are successful. With these kinds of numbers, expect marijuana to remain a hot topic for a long time to come.