WASHINGTON - As Americans count down to the 2016 presidential election, here are some key figures about the world's biggest economy, where the role of immigration, minorities, growth and income disparity have all featured prominently on the campaign trail.

Number one, or three?

The United States is the world's third largest country, both in terms of geographical size and population. Both Russia and Canada cover more ground, while China and India count far more than America's 325 million inhabitants. The US economy nonetheless outpaces all others, with a gross domestic product of $17.9 trillion in 2015, well ahead of both China and Japan.

17.6% Latinos, 13.3% blacks

Non-Hispanic whites still represent a majority of the US population at 61.6 percent, but they are on the decline as the baby-boomer generation grows old. Latinos comprise around 17.6 percent and have overtaken African Americans who now represent 13.3 percent. Asians account for 5.6 percent while Native Americans, including those from Alaska and Hawaii, comprise just 1.4 percent.

Eligible voters

Around 225 million people will be eligible to vote in the November 8 election. Data from the 2012 presidential poll shows that only 71 percent of those eligible actually registered to vote, and just 53.6 percent of eligible voters cast ballots.

11 million undocumented

In 2014, legal immigration added 1.3 million people to the US population, an increase of 11 percent from the previous year. The number of undocumented immigrants in the country is estimated at 11 million, most of whom are of Mexican origin. They are thought to number almost seven million in California alone.

Five percent unemployed

In September 2016, US unemployment stood at 5.0 percent, half the most recent peak recorded in 2009. Median household income was $56,516 in 2015, an annualized rise of 5.2 percent and the first increase since the Great Recession of 2008. The figure is still 1.6 percent lower than in 2007, when the global financial crisis first erupted, and 2.4 percent below the comparable level in 1999.

The rich get richer

In the three decades from 1983 to 2013, the median revenue of upper-income families in the US doubled from $318,100 to $639,400. That is 6.6 times that of middle-income families, which rose only slightly, from $94,300 to $96,500 in the same period. Last year, 13.5 percent of US households lived below the poverty line with income of less than $15,391 for a couple. The proportion of people living without health insurance edged lower in 2015 to 9.1 percent of the population, or 29 million people.

Religion

Almost 71 percent of US inhabitants described themselves as Christian in 2014, including nearly 21 percent who identified as Catholics and 47 percent as Protestant. Jews accounted for nearly two percent of the population, double the rate of Muslims.

Those who checked the "unaffiliated" box represented almost 23 percent, a sharp increase from 2007, when they made up 16 percent of the American population.