The ruble fell, extending the longest weekly slump since November, and bonds declined as the selloff in oil drove the price of Brent to a three month-low. A dollar-denominated gauge of stocks entered a bear market. Russia’s currency weakened 1.1 percent against the dollar to 58.4980 by 6:47 p.m. in Moscow. It declined 2.6 percent this week, the most since the period ended June 7. The RTS Index extended the retreat from its peak in May to more than 20 percent. Oil, which along with natural gas accounts for half Russia’s revenue, has tumbled in London and entered a bear market in New York amid a persisting surplus. The ruble’s correlation with oil rose to 0.47 this week, the highest level in two years, according to data compiled by Bloomberg. “The ruble is a petrocurrency, and oil is on another leg down,” Vladimir Miklashevsky, a strategist at Danske Bank […]