Immigration has always been offset by emigration: at times this was of great concerns of governments intent on filling up the country, particularly the western provinces. The United States was overall the primary destination followed by reverse migration. As a result, the population of Canada at Confederation (1867) was 3.75 million, or 10% of the US population, an average that maintained from about 1830 to 1870. This number would drop to 6% by 1900 due to large emigration to the US, despite large-scale immigration to Canada. Emigration to the US was only 370,000 in the 1870s; averaged a million a decade from 1880 to 1910; almost 750,000 from 1911 to 1920 and 1.25 million from 1921 to 1930. They consisted of both native-born Canadians and recent immigrants from various, mostly European nations. Between 1945 and 1965, emigration to the US averaged 40–45,000 annually. It was not until 1960 that the population of Canada reached the 10% mark again, or 18 million.