In a time before quantitative easing, central banks and policy makers could look to fixed income or Treasury markets as a measure of health for the economy. Today, with central banks around the world engaged in asset purchases of Treasuries, fixed income and equities, those markets have been "polluted" at least for a time, by something other than strictly supply and demand.

As former Federal Reserve Governor Kevin Warsh explains, there are still some markets that have remained unpolluted, and are therefore still a reliable barometer for central bankers and policy makers.

"There are very few markets that are in some sense unpolluted, or less polluted," says Warsh. "The commodities markets and precious metals markets are one of those few markets where central bankers and policy makers can still try to distill signs rather than just looking at a reflection of government policy."

Watch Warsh's full remarks in the above video, and watch parts one and two of our conversation with Warsh.

(This article is sponsored and produced by CME Group, which is solely responsible for its content.)

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