Another week, another dip in the market.

Disappointing news about China’s economy, U.S. jobs, the BP (NYSE: BP) oil spill and the ongoing European debt crisis have sent major indices to new lows and have investors wishing for better days.

But before throwing in the towel, investors should know that there is a simple way to escape the turmoil in the market. A simple ratio — one that is ignored far too often — is the key.

It’s called beta.

Simply put, beta is a measure of a stock’s volatility compared to the overall market. It’s basically a way to measure the risk involved with owning a particular security. And with the kind of volatility we’re seeing in this market, I don’t think anyone should buy a single stock without first knowing its beta.

Here’s how it works:

As stated, beta is calculated by comparing a stock’s return over a certain period of time to the broader market, usually the S&P 500. So let’s say, for example, the S&P gains +10% in a given period, while Microsoft (NYSE: MSFT) gains +15%. This would mean that Microsoft has a beta of 1.5.

#-ad_banner-#Generally speaking, a stock with a 1.0 beta moves along with the overall market. Naturally, investors looking for outsized returns might look for stocks with high betas in a bull market. But when the market is tanking, that’s exactly the opposite of what we want. In this market, it’s a good idea to find stocks that have as little correlation to the overall market as possible.

To find safety from the market — and hopefully a little price appreciation, too — the StreetAuthority staff screened for S&P 500 stocks with a beta of 0.75 or less since May 5th, the day of the “Flash Crash.” This means the stocks that turn up will be at least 25% less volatile than the S&P 500.

Here’s a look at what we found:

Plenty of food and beverage names in this list, and frankly, I’m not surprised. What is surprising, however, is that the food and beverage stocks in this table are up an average of about +10%. The S&P is down about -9% in the same period. If you stuck with defensive names like these, you’re probably pretty happy.

If you think the market will remain in the doldrums, some of the stocks on this list might make for good defensive holdings.

Here’s my take on two stocks from the list that could be attractive additions to your portfolio:

Newmont Mining (NYSE: NEM) is the second-largest gold producer in the world. The company doesn’t carry the geopolitical risks of some of its rivals, as the majority of production comes from the United States, Australia, Peru and Indonesia. Gold, as you may know, has been on a long, sustained bull run — and Newmont’s shares have been a clear beneficiary.

Action to Take –> Newmont’s shares have remained flat while the market has backtracked, but that’s better than most. Also of note: the company does not hedge its production, so it’s fully exposed to fluctuation in gold prices. And given gold’s recent run, the firm’s next quarterly numbers should be impressive.
———–

As auto sales have declined and the public lost faith in the likes of GM and Chrysler, AutoZone (NYSE: AZO) has prospered. People adopted a do-it-yourself attitude and flocked in droves to the company’s 4,400+ stores during the downturn for parts and accessories in order to save on auto repairs or, even worse, having to buy a new car.

This is a growth stock with defensive characteristics. Sure, it’s been a good name to own during a downturn, but there are plenty of reasons to like it even if the market turns around. For starters, AutoZone is venturing into the fast-growing commercial market by offering delivery of parts to garages and dealerships across the country. It’s also expanding south of the border, where there’s no national auto parts chain to speak of.

Action to Take –> The average age of cars on the road is a little over 10 years, according to Morningstar. Consumer confidence is low and if auto sales remain sluggish amid fears of a double-dip recession, the stock looks like a good name to own.

And aside from its growth prospects, the company is also a good steward to shareholders. The company has spent more than $8 billion on share repurchases since 1998 and more than $1 billion in the past year alone. Another $500 million in repurchases are in the works, so even if growth remains flat, the stock’s per-share numbers will look good.