DAVID KOTOK: There Are Three Big Things In The World That Are Worrisome Right Now

David Kotok of Cumberland Advisors has a great note about the recent selloff.

He starts by noting that a lot of clients right now are asking the simple question: "Are you concerned about the market?"

His reply to that is of course, there is never a time when they're not concerned about the market.

But beyond the weak price action lately (largely concentrated, he notes, in biotech, healthcare and tech) there are three big stories that concern him globally. They are: Ukraine, China, and oil.

With markets, the evolution of events can be shaped by exogenous shocks, but effects are limited if such shocks are contained. One of those is Vladimir Putin's flexing of Russian might in Ukraine.

Another, and perhaps more important than Ukraine, is China's slowing growth rate and the question of whether or not a meltdown is taking place in its credit system. China is the world's second largest economy behind the U.S. It is the world's largest goods producer so a slowing has vast implications for commodity pricing and for trade relations between China and other emerging markets countries. Let me quote a good friend and China expert, Michael Drury, Chief Economist of McVean Trading & Investments, LLC. Michael wrote this in today's letter. " The most recent trade data suggest that the deceleration is much more pronounced than the consensus is apparently willing to consider. Moreover, the confidence that the government can solve any problem is so pervasive that it can only lead to disappointment."

A third exogenous shock risk is the political unrest affecting the energy-related oil patch, including Libya, the Persian Gulf, and Nigeria. The external risk profile rises in this very important sector, and that elevated risk is reflected in an oil price that remains above $100.

Of the three, China and oil are very well known. Ukraine is really the geopolitical wild card that nobody can assess well.