This paper examines the evolution of drug use in Colombia over the past years. Our analysis, based on surveys from the Dirección Nacional de Estupefacientes, shows that drug consumption grew substantially between 1996 and 2013. The growth occurred for both genders, all ages, socioeconomic...

We develop a model of vertical merger waves leading to input foreclosure. When all upstream firms become vertically integrated, the input price can increase substantially above marginal cost despite Bertrand competition in the input market. Input foreclosure is easiest to sustain when upstream...