US DATA : wiseGEEK

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More than 26% of people in the US live alone -- twice the percentage from
40 years ago.

According to the US Census, 7.7% of US residents lived alone in 1940 as
compared to 26.7% in 2010. One person households increased with each Census
since 1940 with the greatest jump occurring in the 1970s. In 1970, 17.6% of
Census respondents indicated that they lived alone. By 1980, 22.7% were
living alone, an increase of 5.1%.


http://www.wisegeek.com/how-has-the-number-of-people-living-alone-changed-over-time.htm?m
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