A growing share of Americans say illegal drugs are a big problem in the U.S., a new Gallup poll reveals.

The percentage of adults describing the issue of illegal drugs as “very” or “extremely” serious rose from 65 percent in 2016 to 71 percent in 2017.

These views changed the most among Americans aged 18 to 29 (with 61 percent now saying the illegal drug problem is “very” or “extremely” serious versus 46 percent who said so in 2016) and nonwhites (73 percent in 2017 vs. 57 percent in 2016).

Americans with incomes under $30,000 (35 percent) and those in small towns or rural areas (38 percent) are most likely to say drugs are a big problem where they live.

The findings are from Gallup’s annual Crime poll, conducted in October.

According to Gallup, an “increase in the abuse of synthetic opioids has contributed to making the current drug crisis the deadliest in U.S. history.”

 “Last year, about 64,000 people in the U.S. died as a result of drug overdoses, up from 52,404 in 2015, making drug overdoses the leading killer of Americans under the age of 50,” the report says.