Alternate Views: Get Data, FAQ, ISO Rubric, CSW, HTML, Components, XML US Historic Declination Calculator This programs derives a table of secular change in magnetic declination for a specified point in the conterminous United States. It utilizes the USD polynomial and the IGRF spherical harmonic models. Declination is shown to the nearest minute so that secular change may be properly illustrated, but it is usually only accurate to within 30 minutes. Get the Data Access Format(s) Distributor(s) / Contact Info Instructions / Constraints HTML Format Format version: 1 Format specification: The Declination Calculator creates an HTML pop-up window which superimposes a compass rose, indicating the declination, onto the location queried and reports the annual change in declination. XML Format Format version: 1 Format specification: The Declination Calculator creates an XML file which reports the location and date queried as well as the declination and the annual change in declination in decimal minutes per year. CSV Format Format version: 1 Format specification: The Declination Calculator creates an Comma Seperated Variable (CSV) file which reports the location and date queried as well as the declination and the annual change in declination in decimal minutes per year. DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce Fees None Use Limitation Produced by the NOAA National Geophysical Data Center. Not subject to copyright protection within the United States. Legal Constraints