Legal Minimum Wages and the Wages of Formal and Informal Sector Workers in Costa Rica

The classic dual economy models of developing countries hold minimum wages (among other institutions) accountable for persistent dualism. They note that applying or enforcing minimum wage laws in only one sector of the economy will create wage differentials which will not be eroded with labor mobility to the high wage sector. In this paper we use 12 years of micro data on thousands workers living in Costa Rica to test whether legal minimum wages have a differential impact on the wages of workers in the formal sector vs. informal sector, defined in various ways in accordance with the dual development models. The evidence from Costa Rica is contrary to the assumptions of these models. We find that increases in minimum wages not only raise the wages of workers in the urban formal sector (large urban enterprises) who are covered by minimum wage law, but they also increase the wages of all other workers covered by minimum wage legislation in what are traditionally regarded as informal sectors and where the legislation is often considered not to be enforced. Specifically, we provide evidence that minimum wages increase the wages of workers in small urban enterprises, large rural enterprises and small rural enterprises. Further, our results suggest that higher legal minimum wages raise the average wage of workers in these "informal" sectors more than in the urban formal sector. We concluded that in Costa Rica minimum wages are being enforced in the rural and small scale sectors and may actually work to reduce average wage differentials between these sectors and the urban formal sector. On the other hand, minimum wages have no significant impact on the wages of workers in another sector that is regarded as informal but which is not covered by minimum wage legislation: the self-employed workers (both urban and rural). Thus, one could argue that minimum wages may contribute to dualism between the formal and informal, defined as self-employed vs. salaried workers. However, we find no evidence of the bleaker scenario, that self-employed earnings are being lowered by minimum wages.