A contributing factor to lower household growth was a drop in household headship rates caused by “doubling up.” In other words, some people were forced into combining households to save money during difficult financial times, possibly due to loss of their home or by foreclosure. Household headship rates for all age groups have also fallen since 2005, especially among those under age 35.

Of course, what is going to happen to headship rates in the future remains uncertain. If economic conditions and the foreclosure crisis do not improve, rates may continue to fall. But given the improved affordability conditions, employed workers may soon form households and thus boost headship rates. In most cases, doubling up is only a temporary solution for people — they will eventually prefer to find their own places to live.

The good news, according to the Joint Center, is that the “echo-boom” generation — those born between 1986 and 2005 — will have a tremendous impact on starter homes over the next 15 years. The echo-boom generation, currently at 80.8 million, is even larger than the baby-boom generation. It is projected to grow to 92.9 million by 2025. Meanwhile, baby boomers will boost demand for senior housing.