The surge in immigration to the U.S. since 2021 has been the largest in history, according to an analysis of government data by The New York Times. The annual net migration numbers reveal that, from 2021 to 2023, an average of 2.4 million immigrants arrived in the U.S. per year.

Those immigration numbers surpass the immigration boom of the late 1800s and early 1900s. This figure includes both legal and illegal immigrants.

The Times reported that during the 1850s, when the U.S. Census first began collecting statistical data, the country saw a net increase of 190,000 immigrants per year, or about 0.6% of the total population.

Between 2020 and 2023, that number exceeded 2 million migrants annually, maintaining the same percentage of about 0.6% of the U.S. population.

According to The Times, the share of the U.S. population that is foreign-born reached a new high of 15.2% in 2023. That’s up from 13.6% in 2020. The previous high was 14.8% in 1890.

The immigration surge has been driven by a variety of factors, including the Biden administration’s loosening of immigration policies, which were implemented to counter the more restrictive stance taken by President Donald Trump during his first term.

Under the Biden administration, it has become easier for asylum-seekers to cross the border. Experts said this has resulted in millions of migrants waiting years for their cases to be heard in immigration court.

According to data from TRAC (Transactional Records Access Clearinghouse) in December 2023, the immigration court backlog surpassed 3 million pending cases. The data also showed an average of 4,500 cases per immigration judge. For context, the total number of pending cases was just over half a million in 2016.

In addition to policy changes, external factors such as violence in countries like Haiti and Venezuela have forced many people to leave their homes in search of a better life.

Immigration has been one of the biggest issues for Americans during this year’s presidential election, according to exit polls. President-elect Donald Trump has promised mass deportations, stricter immigration policies, and enhanced border security.

The Times said it used a combination of Census and congressional budget data and collaborated with government experts and Federal Reserve specialists to pair and analyze the immigration data.