Since the 1990s, crime rates in the US have plummeted — with the murder and violent crime rates dropping by more than half.

Americans, it turns out, have no idea.

A new Vox/Morning Consult poll measured how nearly 2,000 registered voters perceive crime both in their neighborhoods and in America more broadly.

The poll found that 69 percent of US voters think there is more crime in the US than there was two decades ago, with 43 percent saying there is “much more” crime and 26 percent saying there is “somewhat more” crime.

Broken down into specific crimes, a majority of Americans said there was more violent crime, drug crime, theft, and white-collar crime.

In reality, various types of crime have plummeted, based on the official FBI figures. The violent crime rate has fallen by more than half, with the murder rate dropping from 9.8 per 100,000 people in 1991 and 8.2 in 1995 to 4.9 in 2015. Rape, robbery, burglary, and theft rates have all also dropped. (There aren’t good statistics for drug and white-collar crimes.)

Rates of crime, particularly murder, did go up in 2015 compared with 2014, but only after 2014 saw the lowest levels of crime in decades. (We don’t really know why the murder rate in particular rose sharply from 2014 to 2015. For more, read Vox’s explainer.)

But Americans were in fact less likely to say crime had dramatically risen in the past year than they were when comparing crime rates with those of two decades ago. The poll found that while 69 percent of voters said that crime had risen in the past year, only 36 percent said there was “much more” crime and 33 percent said there was “somewhat more” crime compared with one year ago.

Americans also don’t seem to realize what types of crime have risen in the past year, with roughly the same saying that rates of violent crime and theft have gone up over the past year. In reality, property crime rates in 2015 dropped to the lowest point since any time after 1966 — while it’s violent crimes that went up for the year.

Americans think their neighborhoods are safer than the US as a whole

Despite the fairly negative outlook voters seem to have on safety across the country as a whole, they have sunnier views of the places they have a more direct experience with: their neighborhoods.

When asked about crime in their neighborhoods, only 37 percent said it was higher than it was a year ago. A greater proportion of voters (39 percent) said it was about the same, while 17 percent said it was less.

But they were a little more pessimistic about the long-term trend: 42 percent said there was more crime in their neighborhoods compared with two decades ago, while 23 percent said it was about the same and 17 percent said it was less.

This is very typical for this type of polling. For decades, Gallup has asked Americans if they think crime has gone up over the past year in their area and the US. Generally, Americans are much more likely to tell Gallup that crime has increased in the country as a whole than they are for their neighborhoods.

There’s a simple explanation for why: Since crime really has been dropping, Americans are very likely to see the improvement in their neighborhoods. But once pollsters start to pull out to bigger, more abstract concepts — crime in the whole country or over the past couple of decades — respondents are likely relying on foggier memories and feelings that reflect more what they see in the news, which tends to be pretty grim, than what they’ve experienced firsthand.

Americans’ inability to recognize the crime drop could have bad policy consequences

Whatever the explanation, these poll results are likely bad news for criminal justice reformers.

Over the past few years, there has been a concerted push to reduce America’s massive prison population. There’s a very good reason for that: America locks up people at a higher rate than any other country in the world, save the tiny African country of Seychelles. And the criminal justice research strongly suggests that the high imprisonment rate is not actually making the country safer, but it is costing us a lot — about $80 billion a year — to keep all these people in prison.

As a previous poll by Morning Consult and Vox found, Americans are generally likely to support reducing the prison population — but only for nonviolent offenses. One reason for that is Americans may think the country’s violent crime rates are still trending in the wrong direction — making them cautious of taking any steps that could, in their views, heighten the risk of more crime.

The reality is, of course, different. But if Americans don’t know that, then policymakers may be skeptical of making changes that could inspire backlash from a misinformed electorate.

Morning Consult polled 1,989 registered voters on October 5 and 6, 2016. The interviews were conducted using large, established online survey vendors and were weighted to approximate a target sample of registered voters based on age, race/ethnicity, gender, educational attainment, region, annual household income, homeownership status, and marital status. Results from the full survey have a margin of error of +/- 2 percentage points. Topline results are available here, and cross-tabulation results are available here.