$EWZ Call Buyers Score

Option traders are posting big profits today in bullish positions opened on the Ishares Msci Brazil ETF (EWZ).

On Sep. 30, Market Rebellion’s Unusual Activity Service found that 11,250 30October 42 calls were bought for $0.97 to $0.72 above the existing open interest of 4,587 contracts with shares at $37.46.

Those calls have traded for up to $2.79 so far today, a 187.63% return, while the stock rose 15.24% in the same time frame, showing how quickly options can far outpace gains in their underlying shares.

Long calls lock in the price where investors can buy a stock, letting them position for a rally at limited cost with the potential for significant leverage. They carry less risk than owning shares because the most that can be lost is the price of the options no matter how far the stock might fall.

The EWZ was last up 13.35% at $43.29 in afternoon trade.