It seems that anxious investors in these troubled economic times are seeking safety in crowds.

The prices of stocks, bonds and a host of other financial assets, which in normal conditions more often than not move in a diversity of unpredictable directions, are increasingly surging up or down in lockstep.

The rise in correlation between individual stocks, but also between completely separate asset classes like stocks and gold or stocks and oil, “has been one of the big themes of the investment climate this year,” said Marc Chandler, a market strategist at Brown Brothers Harriman in New York.

The chief explanation for the correlation is the great uncertainty facing investors — mainly over the crisis in Europe, which has raised the specter of the potential bankruptcy of governments and a collapse of the banking system.

With every bit of bad news, nervous investors around the globe have been selling many of their positions across all asset classes, no matter what they are, driving prices down, and rushing into perceived safe havens like cash and United States bonds. But sometimes just a day or so later, with a glimmer of hope that Europe is pulling away from the abyss or that the United States is picking up steam, newly optimistic investors turn around and rush back from cash into harder assets, like stocks, foreign bonds or commodities, pushing prices higher together.