The yield curve is one of the most and best used instruments in the global macro investors arsenal. The yield curve is usually thought of as a bond traders tool but good global macro trader know better. You can use the yield curve to trade bonds, stocks, currencies, and really just about anything that affects the economy, heck you can even use to for refinancing your home.
The Treasury yield curve is the curve you get when you plot out the yields for different maturities. For instance if the 90-day T-Bill is at .2 percent and the 10-year T-Note is yielding 3.5 percent you have an up sloping yield curve as the long dated Treasuries are paying a higher yield then the short dated Treasuries. Usually you would also plot out the two year, five year, and thirty year along with the ninety day and ten year. This will give you a better picture for what the yield curve is really saying.
This is great but how do you use it to make money? Well the global macro investor knows that if the curve is sloped from the lower left to the upper right that things are looking good for the economy. If on the other hand it is sloping downwards the Fed has tightened and the economy is or will be slowing.
So why does it work? Why does it matter what direction the yield curve is? Well if the yield curve is steep, going form the lower left to the upper right it means that banks are highly incentivized to lend money and therefore spur growth in the economy by helping businesses and individuals spend money on expansions as well as spending in general. This happens because when the curve is upwards sloping banks can borrow short term at low rates from the government and lend at higher rates for longer periods of time to the public.
If the curve is inverted however business is usually about to slow down, rates will be lowered, and bonds will climb. This is because with the incentive of the banks to lend now gone they will throttle back and the spigots of available money run dry. In turn this forces the Fed to lower short term rates, the Fed Fund rate, in order to spur business growth once again. When they lower rates bonds inevitably go up.
Bonds are like a lever. When bonds are high yields are low. When yields are low bonds are high. It is like a board on a fulcrum, when one end goes up the other end goes down. This is how bonds and rates are related.
So anytime that you see either of these events happen the global macro investor can start to look for an entry point to either buy or to sell bonds and stocks. If the curve is inverted then you will likely want to start buying bonds and selling stocks as the act of lowering rates will cause bonds to go up. After bonds have gone up and it looks like the Fed is done lowering rates it is worthwhile to look at stocks as the next beneficiary of the rate cuts as businesses can now borrow cheaper and therefore expand faster.
Of course as with all things in the market nothing works every time. In fact the quote history never repeats itself, but it often rhymes is a very appropriate statement. Used along with proper risk controls the yield curve can become one of the global macro investors best timing tools and economic gauges.