Dynamic Yield Curves vs. Standard and Poors (S&P 500)

What were your overall observations of the relationship (correlation) between the Yield Curve and the S&P500 since 1998. Did the Yield Curve Lead or Lag the Peak in the Market? If it did, by how many months? Did the Curve, Flatten or Invert? Prior to the Peak? On the Short or Long end of the Curve? Can you use the Yield Curve to predict stock market peaks and recessions? By how many months?