As more and more people head downtown in U.S. cities across the country, Chicago takes the top rank, boasting the largest numeric gain in downtown residents, according to a recent report from the U.S. Census Bureau.

The report, which compared 2000 and 2010 U.S. Census data, found that Chicago's downtown area had a net increase of 48,000 residents over the 10-year period -- a 36 percent gain.

Comparatively, Washington D.C. had the second largest gain with a 14.2 percent increase, which amounts to 19,502 residents, Philadelphia's downtown area welcomed 20,769 residents -- a 9.7 percent increase -- and New York City saw a 9.3 percent increase of 37,422 residents. (Scroll down to check out where more cities ranked.)

While the boundaries of a city's "downtown" may be up for debate, the report's authors relied on the location of each metropolitan area's city hall as a "useful proxy for the area’s original 'downtown'" or central business district. Chicago's downtown, for example, is defined by the report's authors as the two miles surrounding City Hall on North LaSalle Street, encompassing the Loop.

Overall, Chicago's estimated 2,707,120 population grew by 362,789 people with downtown gains and similar increases on the outskirts of the city. Residents in the 25 to 34 age group, in particular, flocked to outlying areas.

The report also found Chicago's inner suburbs experienced a significant population decline -- something that could be attributed to residents relocating to booming areas.

Though most cities saw increases in their downtown populations, the trend was not universal. New Orleans, for example, experienced a drastic decline of 35,313 "downtown" residents.

(h/t Reddit)

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  • No. 1 Increase: Chicago

    Downtown population increase: 48,288 (36.2 percent). <br> <em>Photo by Nimesh M <a href="">via Flickr</a>.</em>

  • No. 2: New York

    Downtown population increase: 37,422 (9.3 percent). <br> <em>Photo by (vincent desjardins) <a href="">via Flickr</a>.</em>

  • No. 3: Philadelphia

    Downtown population increase: 20,769 (9.7 percent). <br> <em>Photo by Garyisajoke <a href="">via Flickr</a>.</em>

  • No. 4: San Francisco

    Downtown population increase: 19,712 (5.9 percent). <br> <em>Photo by ArtBrom <a href="">via Flickr</a>.</em>

  • No. 5: Washington, DC

    Downtown population increase: 19,502 (14.2 percent). <br> <em>Photo by Reading Tom <a href="">via Flickr</a>.</em>

  • No. 1 Decrease: New Orleans

    Downtown population decline: 35,313 (30.4 percent). <br> <em>Photo by Reading Tom <a href="">via Flickr</a>.</em>

  • No. 2: Baltimore

    Downtown population decline: 10,194 (6.1 percent). <br> <em>Photo by phil_g <a href="">via Flickr</a>.</em>

  • No. 3: Dayton

    Downtown population decline: 10,165 (19.8 percent). <br> <em>Photo by dospaz <a href="">via Flickr</a>.</em>

  • No. 4: Toledo

    Downtown population decline: 10,118 (15.4 percent). <br> <em>Photo by Ohio Office of Redevelopment <a href="">via Flickr</a>.</em>

  • No. 5: Saginaw, Mich.

    Downtown population decline: 9,674 (19.5 percent). <br> <em>Photo by Saginaw Future <a href="">via Flickr</a>.</em>

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