Projection of Two-Wheeler Vehicle Fleet in India using Road Density per Capita for Accurate Emission Estimation

GDP per capita is commonly used as the main explanatory variable for estimating the on-road vehicle stock. This study explores the use of road density per capita of a country as the main explanatory variable. Results prompt road density as a better explanatory variable than GDP (in PPP terms) per capita for projecting two-wheeler fleet size in India. A higher coefficient of determination was found for the road density-only based model (in the range 0.978-0.988) as against GDP-only based model (in the range 0.880-0.945).