American adults' national pride has hit its lowest point to date, according to the most recent Gallup poll.

The historical pride readings peaked around 69% to 70% following the 2001 terrorist attacks, but the percentage of Americans expressing “extreme pride” in their country has been declining since the start of former President George W. Bush’s second term. Since then, fewer than 60% of Americans have reported feeling extremely proud to be American, according to Gallup.

The current reading shows a drop to 45% of proud Americans — two percentage points lower than last year.

The significant decline in recent decades is largely influenced by Democrats, whose latest 22% extreme pride reading is the lowest in Gallup’s 19 years. It’s also half of what it was months before President Donald Trump’s 2016 victory. Republicans, on the other hand, had a 76% extreme pride reading in the new poll. When former President Barack Obama was in office, Republican pride never fell below 68%, according to Gallup.

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To better understand the sources of Americans’ pride, analysts asked survey respondents whether eight aspects of the government and society make them proud. While a majority expressed pride in scientific achievements, the U.S. military, American culture and arts, sporting and economic achievements and cultural diversity, only 32% of adults reported pride in the American political system. And only 37% said they were proud of the U.S. health and welfare system.

About the poll: Results for the new June 3-16 Gallup poll are based on telephone interviews with a random sample of 1,015 U.S. adults in all 50 states, plus the District of Columbia.

More about the readings at news.gallup.com.