Stay up to date on all defensive stocks with Benzinga Pro, your go-to stock market research platform with real-time news and actionable insights.The S&P 500 index is regarded as the barometer of U.S. stock market performance. Composed of large-cap U.S. equities, the S&P 500 index is often used as a benchmark for professional and retail investors to compete against. When it comes to funds, the SPDR S&P 500 ETF (NYSEARCA: SPY) is the largest and most liquid exchange-traded fund (ETF) for tracking the S&P 500. Here are the best defensive stocks with low correlation to SPY.One investment strategy with the potential to outperform over long periods is buying stocks that have a low correlation coefficient to SPY. This metric is primarily measured by the stock's beta, which also incorporates measures of the stock's volatility. The market (in this case, the S&P 500 or SPY) has a beta of 1.0, while stocks can have a beta of:Above 1.0, meaning that the stock generally moves in the same direction as the market and in a more volatile fashionBelow 1.0 but higher than 0.0, meaning that the stock generally moves in the same direction as the market but in a less volatile mannerAt 0.0, meaning that the stock generally moves in a way uncorrelated to the movements of the marketBelow 0.0, meaning that the stock moves inversely to the market and in a more volatile fashion as it gets more negativeQuick Look at the Top Performing Defensive Stocks:TickerCompany±%PriceInvestGISGeneral Mills0.3%$33.26Buy stockMRKMerck & Co– %$119.99Buy stockPGProcter & Gamble0.36%$143.47Buy stockAMTAmerican Tower0%$184.95Buy stockBMYBristol-Myers Squibb0.02%$58.04Buy stockMCDMcDonald's0.22%$279.88Buy stockDeep DiveThe following defensive stocks all have a low correlation coefficient (beta of 0.50 or under) compared to the SPY. In addition, these stocks exhibit sound fundamentals in the form of positive return on equity; return on assets; return on investment; and gross, operating and net margins. They also have positive historical earnings and revenue growth. A combination of quality characteristics plus a lower-than-average beta makes these stocks potential defensive picks.