Until 1979, the evidence linking El Nino with changes in rainfall around the world came from rain gauges measuring precipitation over land and a handful of islands. Before the launch of the Tropical Rainfall Measuring Mission (TRMM) in November 1997, the remote sensing evidence gathered since 1979 was confined to ocean rainfall because of the very poor sensitivity of the instruments over land. In this paper we summarize the results of a principal component analysis of TRMM's 60-month (1/98-12/02) global land and ocean remote-sensing record of monthly rainfall accumulations. Contrary to the first principal component of the rainfall itself, the first three indices of the anomaly are most sensitive to precipitation over the ocean rather than over the land. With the help of archived surface station data, the first TRMM rain anomaly index is extended back several decades. Comparison of the extended index with the Southern Oscillation Index shows that the first principal component of the rainfall anomaly is strongly correlated with the El Nino / Southern Oscillation indices.