The U.S. Census Bureau has conducted the Residential Finance Survey (RFS) as part of the decennial census since 1950. The survey collects data that measures the levels of residential mortgage debt and assesses the effectiveness of the current residential finance system.

The RFS is a unique survey for several reasons:

• It collects, tabulates, and presents data for properties - the standard unit of reference for financial transactions related to housing. In most other demographic surveys, the unit of reference is the person, household, or housing unit.
• It is the only source of information on property, mortgage, and financial characteristics for multi-unit rental properties. Information on multi-family loans and properties is particularly difficult to obtain, but is important to understand if progress is to be made in the development of standards for underwriting multi-family mortgages.
• It conducts interviews of property owners and mortgage lenders, resulting in more accurate information on property and mortgage characteristics. The RFS is the only survey which is able to provide a comprehensive view of mortgage finance in the United States, by providing information not only about the loan itself from the lender, but also information about the property owner's demographic characteristics.
• As part of the decennial census, it is mandatory. This is important in collecting information from mortgage lenders. The RFS is exempt from statutes prohibiting release of financial records by financial institutions.
• It is able to subdivide the industry into relevant components. Different parts of the industry have excellent information on their own loans and clients, but not that of the industry as a whole. Information on lending by individual investors or small groups of investors, such as pension funds, is collected only by the RFS.