This report provides methodological details on the estimates presented in Adding It Up: Investing in Contraception and Maternal and Newborn Health, 2017 and related publications, and includes detailed national and regional data. Adding It Up is an ongoing Guttmacher Institute project in which researchers estimate the need for and the use, costs and impacts of various sexual and reproductive health services for developing countries. Estimates have thus far been produced for 2003, 2008, 2012, 2014 and 2017; 2016 estimates focusing on adolescents are also available. While the basic Adding It Up methodology remains unchanged, this report details recent revisions to some of the estimation approaches.