The effect of governmental systems on politic economy: A study of OECD and G20 countries

The subject of this thesis is the effect of presidential and parliamentary systems on the economic performance of countries. The effect of governmental systems on economic performances are studied through the 34 member countries of the OECD and the 20 members of the G20. The study makes a comparative analysis of economic performances attained in these member countries, governed either by presidential or parliamentary systems, between 2001 and 2015. Since it would not be possible to inspect the governmental structure features of each and every member of OECD and G20; USA and UK are taken as basis in this study of governmental systems since they strike as the models where such systems appear to be implemented the best. Additionally, differences in countries which use the same system are also mentioned. Economic performances are compared on basis of such macroeconomic performance indicators as GNP, national income, growth, unemployment, inflation, current account balance and foreign investment as well as the "Index of Economic Freedom" by The Heritage Foundation. The data set published by the OECD and the World Bank was utilized throughout the research process. The analyses used the ratio, rate and trend analysis methods. In terms of political economy, many political, economic and international factors are involved in economic performance. Among political factors; governmental systems play a particularly significant role in addition to political parties, election systems and institutional structures. Inflation, unemployment, interest rates and exchange rates are prominent economic factors. Additionally; international crises, wars and economic problems strike as major factors affecting economic performance. Our research arrives at the conclusion that both governmental systems have their own superior aspects when it comes to political economy. In terms of growth, share of GNP and unemployment; countries governed with presidential systems present a better economic performance. On the other hand, parliamentary systems attain greater success compared to presidential systems in per-capita income, inflation, current account balance, direct foreign investment and economic freedom index.