 These figures are obtained from a variety of sources, including government election websites, media websites and political party websites.Increasingly, statistics are sent directly to Carr by psephologists, academics and political activists in the countries concerned.The archive also includes Carr's original electoral maps at constituency level for a number or countries, including Australia, Canada, France, Germany, India, Japan, Mexico and the U.S.. 

Matthew M. Singer, a specialist in election studies at Duke University, wrote