EWZ Fighting Off Petrobras Woes

Shares of the iShares MSCI Brazil Index Fund

are up 1.4 percent today despite continued declines for Petrobras

, the ETF's largest holding. Two Petrobras securities combine for 16.1 percent of EWZ's weight. As such, Brazil's state-run oil producer has often been viewed as a primary driver of the ETF's price action

. Petrobras American depositary receipts are off almost four percent in the past five trading days as traders have pressured the oil giant following a weak third-quarter earnings report released last Friday. Due to the closure of U.S. markets on Monday and Tuesday because of Hurricane Sandy, Petrobras ADRs traded for the first time after the earnings report on Wednesday. Earnings slid 12 percent while analysts expected a 20 increase and output declined. "This is probably the worst set of data ever seen from the company," Credit Suisse said,

. While some traders and investors believe EWZ, the largest ETF tracking Latin America's largest economy, are joined at the hip, the correlations are not as tight as some suspect. Over time frames ranging from the last month to the past decade, EWZ has usually outperformed Petrobras, often by significant margins. Making EWZ's sturdiness today all the more impressive is that Greenlight Capital founder David Einhorn

. Brazil's Vale

, the world's largest iron ore producer, represents almost 12 percent of EWZ's weight. For more on ETFs, click

.