Franklin D. Roosevelt is top U.S. president when it comes to economy ATLANTA, Nov. 5 (UPI) -- An analysis of 220 years of U.S. data found Franklin D. Roosevelt the top U.S. president when it comes to the economy, a researcher says. Mark Zachary Taylor, assistant professor in Georgia Institute of Technology's Sam Nunn School of International Affairs, found after Roosevelt, Warren G. Harding, Rutherford B. Hayes, William McKinley and Millard Filmore rounded out the top five with an "A." Our first president, George Washington, received a grade of A-minus. The study, published in the journal Political Science & Politics, found notable presidents such as John Adams, Harry Truman and John F. Kennedy ranked slightly lower in the A-minus/B-plus range, followed by Bill Clinton and Ronald Reagan with B's. "Put simply, if 'it's the economy, stupid,' then we need to make stronger efforts to properly judge economic performance and to assign credit and blame where they are most deserved," Taylor said in a statement. These rankings are meant to constitute a scientific step in this direction. Taylor graded the presidents individually using the traditional A-F scale based on how well each performed in eight economic areas such as unemployment, inflation, interest rates, stock market returns and currency strength. He used multiple and competing statistical measurements, ranking algorithms and time lags to ensure the data was unbiased. No historical or ethical judgments were used to adjust the findings, Taylor said. The study did not include President Barack Obama's first term because it was not completed and the data would not be available until 2015, Taylor said.