Control variables included in tire regression are age, education level and indigenous status. Education levels correspond to the International Standard Classification of Education (ISCED) 1997. For "Low education”, the highest level of educational attainment at ISCED 1997 Levels 0-2 (pre-primary, primary, lower secondary ), for "Moderate education”, the highest level of educational attainment at ISCED 1997 Levels 3-4 (upper and post-secondary), and “High education” indicates the highest level of educational attainment is ISCED 1997 Levels 5-6 (tertiary education).