Americans' level of concern about racism has spiked yet again in the wake of last month's shooting at a black church in Charleston, South Carolina, a new Gallup poll finds.

While just 9 percent of Americans view racism as the most important problem facing the country, that's up from 3 percent in June and the highest that figure has been since 1992, when it reached 15 percent in the wake of riots surrounding the beating of Rodney King by Los Angeles police officers.

Only two issues, the economy and dissatisfaction with the government, were ranked higher in importance, with both tied at 13 percent.

In recent years, the percentage of Americans viewing racism as the nation's most important issue has spiked following several high-profile cases of police brutality. The figure rose to 13 percent after protests in response to the police killings of several unarmed black men and boys, including Michael Brown, Eric Garner and Akai Gurley. It ebbed to a low of 3 percent before rising again to 8 percent in the wake of riots sparked by the death of Freddie Gray.