However, the fact that oil has constantly had to prop up Mexico's weak public finances and that an additional tax burden was imposed on Pemex starting in 1983 are both circumstances that reduced oil investment, especially in exploration, refining, and petrochemical projects.
Sin embargo, el apoyo constante a las débiles finanzas públicas, la carga fiscal impuesta a Pemex desde 1983, ha ocasionado ajustes en la inversión petrolera con impacto negativo, especialmente, en la exploración, refinación y petroquímica.