Well here is a list of countries by net migration rate: https://www.cia.gov/library/publications/the-world-factbook/rankorder/2112rank.html
Note that net migration rate is not completely the same as Immigration rate. It is " the difference between the number of persons entering and leaving a country during the year per 1,000 persons." You'd have to exclude the leaving ones, to get immigration rate. They don't usually do statistics on that. But if a country has high net migration rate, probably not many people emigrate from it.
However, the simple answer is Canada. Part of the Canadian government policy and Canadian identity is the promotion of diversity and in 2010 the immigrantion rates were set at between 240,000 and 265,000 new immigrants, most coming from Asia.
US
You can calculate a country's immigration rate in a manner similar to the calculation of birth and death rates. The immigration rate for Canada is 7/1000 (0.7%)
To calculate the immigration rate, divide the number of immigrants arriving in a country by the total population of that country, then multiply by 100 to express it as a percentage. This will give you the rate at which immigrants are entering the country relative to the total population.
the Answer is Italy.
China China
USA
On its own New Zealand has a birth rate of 1.8 which is below the replacement rate. Without immigration the population would decrease and economic opportunity would diminish. Immigration boosts this rate to 2.2 allowing the country to grow.
The United States has the largest rate of incarceration in the world, with over 2 million people currently in prison.
immigration
The United States of America takes in more immigrants per year than any other country combined. Source below.
Yes unless there was immigration, the country would have a declining population.
The role that immigration plays in population of Canadian country depends on how much immigration is happening in the global surface of Canadian country. The more population = more immigration, therefore meaning that there is also an element of emigration. There are other factors that play a part too, like death rate and birth rate. The more deaths than births, the less populated the certain area will be. VISE-VERSA.