For the first time since the recession, U.S. household income increased significantly during 2015. Gains were seen even among the lowest income households, with the poverty rate declining from 14.8% to 13.5% (Proctor, Semega, & Kollar, 2016). Millions of people, however, continue to struggle economically. Household income for the poorest 10% of households remains 6% lower today than in 2006, and more than 43 million Americans remain in poverty, many of whom struggle to afford their homes. Each year, the National Low Income Housing Coalition (NLIHC) measures the availability of rental housing affordable to extremely low income (ELI) households and other income groups (see Box 1). This year’s analysis is slightly different from previous years in that NLIHC adopted the federal government’s new statutory definition for ELI, which are households whose income is at or below either the poverty guideline or 30% of their area median income (AMI), whichever is higher. Based on 2015 American Community Survey (ACS) data, this report provides information on the affordable housing supply and housing cost burdens at the national, state, and metropolitan levels. This year’s analysis continues to show that ELI households face the largest shortage of affordable and available rental housing and have more severe housing cost burdens than any other group.