In 2011, almost 1 in 5 households included an “additional adult” — someone who was not the householder, the householder’s spouse or cohabiting partner. 

Between 2007 and 2011, the number and percentage of all adults who were additional adults  increased for the nation as a whole and in 40 states.  Using data from the American Community Survey, Census Bureau researchers see some evidence that these shifts in living arrangement had an economic dimension. 

The Census Bureau analysis shows that householders who shared their residence with additional adults had higher individual poverty rates than those who did not, suggesting that those who shared were more economically vulnerable than those who did not. 

The individual poverty rate for householders in shared households was 19% as compared to 15% for those who did not.

For additional adults, the official poverty rates were lower than their individual rates, suggesting that they were more economically secure than they would have been living alone. The official poverty rate for additional adults was 16%.  However based on individual needs and resources, the individual poverty rate of additional adults was 55%.

In addition, among people in shared household, household poverty rates were lower than official rates, showing that additional adults brought necessary resources to the household. The household poverty rate for additional adults was 11%, as compare to the official rate of 16%.

Source:
Macartney, Suzanne and Laryssa Mykyta,Poverty and Shared Households by State: 2011 U.S. Census Bureau, American Community Survey Briefs ACSBR/11-05. Poverty and Shared Households by State: 2011 (PDF). U.S. Government Printing Office, Washington, DC, 2012.  Accessed 7/16/2013