More than a third (35%) of Americans now say they are worried “a great deal” about race relations in the U.S. — which is higher than at any time since Gallup first asked the question in 2001. The percentage who are worried a great deal rose seven percentage points in the past year and has more than doubled in the past two years.

Concern about race relations in the U.S. has risen during an 18-month period marked by a series of deaths of unarmed blacks at the hands of police officers. These deaths sparked major, sometimes violent, protests and fueled the nationwide rise of the “Black Lives Matter” movement.