Longwave Analytics Economic Interpreter Ian Gordon explains the historical significance of the four long economic waves in the United States from June 1789 to the present. By charting yield trends in U.S. Treasurys; U.S. total debt to gross domestic product; the American inflation rate; the price movement in gold equities and the trend in the Standard and Poor's stock price index - all on the same page - investors can readily compare those trends to the long economic cycles delineated as the bottom chart.