Why do long distance truck drivers work extremely long hours?

Abstract

While other research has shown that higher paid truck and bus drivers are safer, this is the first study showing why higher paid drivers are safer. We estimate the labour supply curve for long-haul truck drivers in the United States, applying two-stage least squares regression to a national survey of truck drivers. We start with the standard model of the labour supply curve and then develop two novel extensions of it, incorporating pay level and pay method, and testing the target earnings hypothesis. We distinguish between long-haul and short-haul jobs driving commercial motor vehicles. Truck and bus drivers choose between long-distance jobs requiring very long hours of work away from home and short-distance jobs generally requiring fewer hours. The labour supply curve exhibits a classic backward bending shape, reflecting drivers’ preference to work until they reach target earnings. Above target earnings, at a ‘safe rate’ for truck drivers, they trade labour for leisure, working fewer hours, leading to greater highway safety. Drivers work fewer hours at a higher pay rate and likely have less fatigue. Pay rates also have implications for driver health because worker health deteriorates as working time exceeds 40 hours. JEL Codes: I14, J28, J33, J88, L92, M55