Unions are more effective so that wage rates increase. OPEC successfully increased oil prices. Labor productivity increases dramatically. Enormous natural gas discovery decreases energy prices. Computer technology brings new efficiency to industry. Government spending increases. Cuts in tax rates increase incentives to save and invest. Low birth rate will decrease the labor force in the future. Research shows that improved schools have increased the skills of American workers and managers. Determinants of AS Directional change in AS New AS curve