Diennial is a misspelling of Decennial. It appeared as a header ( now corrected ) at the Census web page. http://library.csusm.edu/subject_guides/history/online_primary.asp See entry text below. "United States Census Bureau Selected Historical Diennial Census: Population and Housing Counts provides selected data from 1790-1860, 1990, and 2000 in PDF format as well as links to Measuring America: The Decennial Censuses >From 1790 to 2000 (the census survey documents) and Historical Statistics of the U.S. (abstracted information from Colonial times to 1970 censuses.)" James -----Original Message----- From: owner-photoforum@xxxxxxxxxxxxxxxxxx [mailto:owner-What does this word mean? I can't find it in my dictionary. Roger On 28 Jan 2010, at 1:22 PM, Emily L. Ferguson wrote: > diennial
