The answer is very few. The US historically has a low emigration rate. Currently immigrants are using Canada to try to get into the US, record numbers of illegal border crossings are happening from Canada to the US.
"Officials for the Swanton Sector in Vermont said there were 1,109 apprehensions in March 2024. According to U.S. Customs and Border Protection figures, this is up from 756 in March 2023, and just 61 in March 2022. The March 2024 figure of 1,109 is higher than the total amount of crossings in all of 2022, which was 1,065."
"In a post on X, Chief Patrol Agent Robert Garcia of the Border Patrol Swanton Sector said the 1,109 apprehensions last month included people from 40 different countries."
"The top three nationalities apprehended were 408 Indian, 323 Bangladeshi, and 170 Mexican nationals," Garcia said.
https://www.newsweek.com/us-canada-border-migrants-crossing-...
"Officials for the Swanton Sector in Vermont said there were 1,109 apprehensions in March 2024. According to U.S. Customs and Border Protection figures, this is up from 756 in March 2023, and just 61 in March 2022. The March 2024 figure of 1,109 is higher than the total amount of crossings in all of 2022, which was 1,065."
"In a post on X, Chief Patrol Agent Robert Garcia of the Border Patrol Swanton Sector said the 1,109 apprehensions last month included people from 40 different countries."
"The top three nationalities apprehended were 408 Indian, 323 Bangladeshi, and 170 Mexican nationals," Garcia said.