Business Dynamics Statistics, BDS
http://www.ces.census.gov/index.php/bds/bds_home

The new Business Dynamics Statistics are a product of the Center for Economic Studies of the U.S. Census Bureau. The annual series describes establishment-level business dynamics along dimensions absent from similar databases including firm age and firm size. The new data series provides researchers with a tool to gain insight into the dynamics of a changing economy. Business Dynamics Statistics are created from the Longitudinal Business Database (LBD), a confidential database available to researchers throughout the network of Census Research Data Centers. The BDS was developed by the U.S. Census Bureau, and partially funded by the Kauffman Foundation. The BDS is unique in that its source data are longitudinal in nature and permit tracking establishments and firms over time. The public use files are created in an effort to make these data accessible to a broad range of data users. Other efforts currently under way include the creation of a fully synthetic microdata file based on the LBD. The BDS series provides annual statistics for 1976-2005 by firm age and firm size. Annual files are also provided at the state level, for Standard Industrial Classification sectors and for the economy as a whole. This has been added to Business Intelligence Resources Subject Tracer™ Information Blog/. This has been added to Statistics Resources Subject Tracer™ Information Blog. This has been added to the tools section of Research Resources Subject Tracer™ Information Blog.