This data release documents three Microsoft Excel tables that contain estimates of tritium in precipitation data for the continental United States. Table 1 contains estimates of tritium in precipitation for precipitation stations located in the continental United States. Measured precipitation data are formatted in regular font while correlated data are italicized. Table 2 contains tritium in precipitation for ninety-six 2-degree latitude by 5-degree longitude quadrangles covering the continental U.S. Latitudes are north of the equator and longitudes are west of the prime meridian. Please see the processing steps below and the main manuscript for additional details on the results presented in this table. Table 3 lists the correlation coefficients used to correlate tritium in precipitation data from Vienna, Austria to the station or quadrangle for dates after January 1, 1987. The coefficient of determination, also known as the R-squared values is listed for each month. Copies of each table also are provided in comma separated formats.