Follow up note sent this morning:

Today's sharp moves up in commodities provides additional evidence that the CME's margin changes have greatly increased volatility.

Furthermore, your arbitrary definition of market volatility lacks credibility because of its short term focus. Let's assume Silver only made it to $30 in 1980, instead of $50. The CPI inflation calculator available at the Bureau of Labor Statistics website informs us that $30 in 1980 is the equivalent of $81.36 in 2011. Please explain how you can justify 5 margin increases in an extremely short period of time when Silver was trading under $50. I find the CME's conduct unacceptable. Many people invest in Silver with hard earned cash that they have saved over the years. Why should the silver they have purchased with cash be subject to such volatile price fluctuations due to your arbitrary margin policies? Do you employ the same definition of volatility to the downside that you employ to the upside? If so, why aren't you dramatically lowering your margin rates to combat this rapid volatility to the downside?