We hear lots of talk about the currently increasing population in DC after decades of decline. What was declining over those decades? The blue line below shows DC's population increasing, with its peak in 1950, after which DC's population does decline. However, the number of actual households in DC (the red line) has remained pretty steady since 1960:
So, the main trend is not a decrease in the number of households in DC, but rather a decrease in family or household size. Those large families that could leave DC for larger houses in the suburbs left. In some cases, large households' homes were destroyed by urban renewal, and families were divided into smaller households in public housing, leaving grandparents to live separately from their grandchildren, etc. The large households were replaced by smaller families with professional breadwinners.
In Georgetown, this change happened with the arrival of New Dealers in the 1930s, who displaced a wide range of large families. With the Second World War and the immense growth of the federal government to wage war, DC's population grew quickly, which can be seen from 1940 to 1950, its peak population size. By 1950, 14.3% of DC households were one-person households. On Capitol Hill, the gentrification process was well underway in the 1970s replacing a whole range of large families with small-sized households headed by professionals. By 2010, 44% of DC households were one-person households.
Since 2000, we do see an increase in both population and the number of households. Next step: from the Census, who are the main groups fueling these increases?