The U.S. Census Bureau expects more than one million immigrants to enter the United States in 2016, and projections to 2050 show that the country may add as many as 49 million new residents over the next three and a half decades.

In its newly released International Data Base, the agency revealed that the net immigration figure for the current year will rise to 1.25 million; that number is calculated by taking the number of new arrivals and subtracting the number of those who leave the country.

In 2016, the net immigration figure is likely to rise slightly to 1.25 million, and it may reach a level of 1.31 million by 2025, the Census Bureau said. Over the next 10 years, 14 million new immigrants -- or eight times the population of New York City's Manhattan borough, are expected to come to the U.S.

Most immigration to U.S. occurs "legally," meaning that foreign citizens eligible for green cards apply for the benefit through U.S. diplomatic posts abroad. The constant rise in the number of new residents admitted is due to 1960s legislation that did away with caps, which had been put in place during the Coolidge administration.

While fewer than 1 in every 21 Americans was foreign-born in 1970, that ratio today has risen to one in seven U.S. residents. Some 80 million Americans, meanwhile, are either children of immigrants or immigrants themselves, according to the Migration Policy Institute.

In the United Kingdom, on the other hand, leaders are increasingly trying to cap the influx of migrants, and Prime Minister David Cameron has proposed lower immigration levels in an effort to cater to Conservative voters in recent parliamentary elections. "I believe we would be a better, stronger country if we had net migration in the tens of thousands rather than the hundreds of thousands," he said.

Americans, however, seem to remain open to immigration and weary about additional curbs, a June poll by ImmigrationWorks USA revealed only 13 percent of those surveyed thought that legal immigrants take jobs away from American workers, while twice that percentage thought they were taking jobs that citizens do not want, Reuters reported.