Which of the following statements about the yield curve for US Treasuries over time, are TRUE:

(Supporting Video if needed can be found on YouTube called "Animated Yield Curve: 1990-2015Q1" .... published on April 15, 2015)

I. When higher maturity treasuries are yielding more than shorter maturity treasuries, the economy has historically headed into a recession (i.e. a leading indicator)

II.When shorter maturity treasuries are yielding more than higher maturity treasuries, it would be prudent to sell some of the stocks in your retirement account and buy some government bonds instead

III. The VIX and TED can be used to measure investors fears about the equity market (i.e. the S&P 500 or SPX) and the bond market, respectively

IV. When higher maturity treasuries are yielding more than shorter maturity treasuries, this is not normal