A new report spells out the economic necessity of a growing immigrant population in the Midwest.

Amid the heated debate about immigration reform there is some nuanced reality: Immigrants are needed in the Midwest to help maintain the economic vitality of metro areas where the number of native-born people is aging and declining.

A report from the Chicago Council on Global Affairs says the region has been harder hit than most: The number of native-born people in the Midwest grew by only 3.3 percent in Midwestern metro areas between 2000 and 2010 while the immigrant population, many of them in their prime working and taxpaying years, rose by 38.4 percent.

According to the report, the 929-person growth in population in Duluth from 2000 to 2010 was 100 percent attributable to immigration. In Minneapolis, 35.2 percent of the growth was attributable to immigration. In Rochester, 20.3 percent was attributable to immigration. In Fargo, 1,022 new immigrants offset much of the loss of the 1,230 native-born residents who left.

It takes into account foreign-born people of various legal statuses, including naturalized citizens, legal permanent residents, temporary visitors who are here to work or study and undocumented immigrants.

The numbers don't reflect the visceral debate that immigration engenders, and its recommendations may be easier said than done in the current political environment. The report calls for encouraging immigration of those able to fill high- and low-skill jobs in places where workers are needed.

It also suggests things such as making it easier to secure financing for mortgages so that immigrants can function as active consumers. It suggests that immigrants eventually be able to vote and participate in other civic duties to be engaged.

"In a region suffering from population slowdown, slow growth and aging, nothing compares to immigration in helping maintain the vitality of metro areas that are home to millions of residents," the report says.