In GPWv3, the population data estimates are provided for the period 1990-2015, by quinquennial years. The population estimates for 2005, 2010, and 2015 were produced in collaboration with the United Nations Food and Agriculture Programme (FAO) as GPW: Future Estimates.
GRUMP datasets are available for 1990, 1995 and 2000
A longer backasted time-series, ranging from 1960-2000, is available in some of the regional, lightly modeled variants of GPW. An updated version of the Africa, Asia, and Latin America (http://na.unep.net/datasets/datalist.php3) – which relied on many of the same inputs as earlier versions of GPW – are available directly from their database developers at UNEP and CIAT.