The 2011 estimates are calculated using data collected from a sample of 46,408 companies with employees and 30,000 businesses without employees. The sample frame for companies with employees was about than 5.7 million, and 29.0 million for companies without employees. For those companies with employees, capital expenditures data are published for 132 industries. In addition, total capital expenditures, with no industry detail, are shown for the businesses without employees.

Beginning with the 2004 ACES, industry categories used in the survey were comprised primarily of three-digit and selected four-digit industries from the 2002 North American Industry Classification System (NAICS). Industry combinations were developed through consultation with data users. In addition, a category was provided for structures and equipment expenditures serving multiple industries; for example, headquarters, regional offices, and central research laboratories.

In 2007, an updated edition of the NAICS was released. 2009 was the first year that industries were sampled and asked to report using this modified system.

Four survey forms (ACE-1(S), ACE-1(M), ACE-1(L), and ACE-2) were used for the 2011 ACES. The ACE-1(S), ACE- 1(M), and ACE-1(L) survey forms were mailed to a sample of 46,408 companies with employees. Recipients of these survey forms were requested to provide capital expenditures data for each industry in which they had activity and to classify these expenditures as new and used structures and equipment.

New structures and equipment include expenditures for new buildings and other structures, structures that have been previously owned but neither used nor occupied, new machinery and equipment, and other new depreciable assets. Used structures and equipment include expenditures for buildings and other structures which have been previously owned and occupied, secondhand machinery and equipment, and other used depreciable assets. In addition, these companies were asked to report new structures and equipment acquired under capital lease arrangements entered into during the survey year.

The ACE-2 survey form was mailed to a sample of 30,000 businesses without employees. Capital expenditures data were requested separately for new and used structures and equipment. (Examples of ACE-1(S), ACE-1(M), ACE-1(L), and ACE-2 survey forms are in Questionnaires and Instructions.)

In accordance with federal law governing Census Bureau reports (Title 13 of the United States Code), no data are published that would disclose the identity or operations of companies providing information. When the estimate for a specific data item cannot be shown without disclosing information for individual companies, the publication of that data item is suppressed. The process of suppression does not change the overall totals, so the integrity of the data is not adversely affected.

The following abbreviations and symbols are used in this publication: