All statistics from the SOMA refer to apartments in newly constructed buildings with five units or more. Absorption rates reflect the first time an apartment is rented or the first time a con­dominium or cooperative apart­ment is sold after completion. If apartments initially intended to be sold as condominium or coopera­tive units are, instead, offered by the builder or building owner for rent, they are counted as rental apartments. Units categorized as subsidized and tax credit are those built under two HUD pro­grams (Section 8, Low Income Housing Assistance and Section 202, Senior Citizens Housing Direct Loans) and all units in build­ings containing apartments in the Federal Housing Administration (FHA) rent supplement program. The data on privately financed units include privately-owned housing subsidized by state and local governments. Time-share units, continuing-care retirement units, and turnkey units (privately built for and sold to local public housing authorities after comple­tion) are outside the scope of the survey.

Additionally, the SOMA tabulates and reports absorption rates for units based on their Core-Based Statistical Area (CBSA). CBSAs include an urban center of at least 10,000 people and adjacent areas that are socioeconomically tied to the urban center by com­muting. The term “CBSA” refers collectively to both metropolitan statistical areas and micropoli­tan areas. Micropolitan areas are based around Census Bureau-defined urban clusters of at least 10,000 and fewer than 50,000 people. Absorption rates within the CBSAs are further divided into “Inside Principal City” and “Outside Principal City.”

Principal cities of a CBSA are the largest incorporated places with a population of at least 10,000 in the CBSA. If there is no such place present in the CBSA, the largest incorporated place or census des­ignated place (CDP) in the CBSA is termed the “Principal City.” Principal cities also include any additional incorporated place or CDP with a population of at least 250,000 or in which 100,000 or more persons work.

Geographic regions. The four major regions of the United States for which data are presented in represent groups of states as follows:

Northeast: Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont.

Midwest: Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin.

South: Alabama, Arkansas, Delaware, the District of Columbia, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia, and West Virginia.

West: Alaska, Arizona, California, Colorado, Hawaii, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming.