A new Thompson Reuters/Jefferies In-The-Ground CRB Global Commodity Equity Index is expected to launch this week, and it says it will help investors bypass futures-based commodity exposure while still playing in the commodity universe.

Kevin Noblet for The Wall Street Journal explains that the index tracks the equity prices of commodity-producing companies, rather than the commodities themselves. Commodity-related equities don’t change in value as monthly contracts expire, so they can skip around the regulation imposed by the CFTC.

About 70% of the companies’ assets are “in the ground,” which is what the name of the index refers to. The companies deal with energy, precious and industrial metals, as well as agriculture products.

ETFs based on the index are in the works from ALPS Advisors and sub-advisor Arrow Investment Advisors.

Matt Kranz for USA Today says that commodity ETFs are fine for investing, so long as investors understand their risks. During inflation, prices rise rapidly, and investors, savers and bondholders all suffer. Commodity-related investments and ETFs are perfect buffers for inflationary periods.

Just beware, however, as commodities prices already reflect current inflation expectations, so you could lose money if inflation is lower than people fear.

Watch the trend lines to protect yourself.

• iShares S&P GSCI Commodity Index Fund (NYSEArca: GSG): up 5.3% year-to-date

• PowerShares DB Commodity Index (NYSEArca: DBC): up 3% year-to-date

• Greenhaven Continuous Commodity Index (NYSEArca: GCC): up 6.5% year-to-date

For more stories about commodities, visit our commodity category.

As this slide continues, an article from The Economist explains that there are reasons to not expect a collapse in raw material prices. There are various explanations for the recent drop in prices, mainly surrounding the dismal economic outlook in wealthy countries.

The slowdown in the wealthier countries leaves them likely to consume less oil, steel, cocoa and many other commodities. However, emerging markets are expected to make up for this slowdown in consumption.

Emerging markets, led by China, now account for the bulk of growth in global demand for raw materials and a good chunk of overall consumption. On top of this, the International Monetary Fund predicts developing countries to grow nearly 7% this year, which should make up for the slowdown of wealthy countries and keep demand for most commodities expanding.

Other factors influencing commodity prices include a number of different circumstances. Some see commodities in general, particularly gold, as a hedge against inflation. These type of investors may sell if their fears about rising prices subside. Also, other investors may sell to cover losses in other markets, or to rebalance portfolios in light of many different factors ranging from falling stock and bond prices to avoiding the repurcussions of American politicians looking to crack down on speculation.

Commodities have also shown a trend to move in the opposite direction of the dollar, which has been climbing recently. However, it seems that as long as economic growth in the developing world continues, there are no true reasons to expect a collapse in raw material prices.

Some commodity ETFs include:

• iShares S&P GSCI Commodity-Indexed Trust (GSG), up 13.8% year-to-date
• GreenHaven Continous Commodity Index (GCC), up 4.1% since January 24th inception
• iPath Dow Jones-AIG Commodity Idx TR ETN (DJP), up 3.5% year-to-date

Investors have realized that prices for things like oil and corn can surge even as the rest of the market spoils. Ian Salisbury for The Wall Street Journal reports that many financial advisors are now keeping a small portion of investors’ assets in commodities to smooth overall volatility in a portfolio.

But constructing an index of commodities can be a challenge. Stock indexes often contain companies weighted by market capitalization – but that’s not possible with commodities. This means index designers have to take a different route, and it yields wildly different results.

Compare the iShares S&P GSCI Commodity Indexed Trust. It has 78% in energy and 2% in precious metals. As a result, it is up higher despite the recent declines in oil. The Greenhaven Continuous Commodity Index has 47% in agriculture and 18% in energy, and it’s up 2% since launching in late January.

Many other commodity ETFs and exchange traded notes (ETNs) sit somewhere between those two extremes.

Index designers have different ways of decided how much of which commodity to include. One way is to estimate how much of a commodity is produced in a year. But commodities are not like equities and the closest thing you can get to market-cap weighting is to estimate production.

• iShares S&P GSCI Commodity-Indexed Trust (GSG), up 11.2% year-to-date
• GreenHaven Continuous Commodity Index (GCC), down 0.3% since Jan. 24 inception
• iPath Dow Jones-AIG Commodity Index TR (DJP), up 2% year-to-date

Since the year is past the halfway mark, it is fair game to start comparing ETFs within the same sector, and ETFGuide compares three funds which track commodities. The commodities sector has been the one of the most successful for 2008, but the three funds are delivering different results.

iShares S&P GSCI Commodity Indexed Trust (GSG) is up 44.8% and uses a passive method for selecting commodities. GSG weights upon world production, measuring the average production over the past five years.

PowerShares DB Commodity Index (DBC) is up 47.1% and has a different process for selecting and weighting which commodities are tracked on the DB Liquid Commodity Index-Optimum Yield Excess Return Index. DBC is composed of futures contracts on six commodities, with 55% toward energy commodities, using a modified equal-weighting strategy.

GreenHaven Continuous Commodity Index (GCC) is up 21.9%, and uses the same passive method for selecting commodities as GSG. GCC follows the Continuous Commodity Index Total Return, an equally-weighted basket of 17 commodities.

As a consumer, the commodities boom can make you feel pinched, but the bull market of raw materials is a tremendous investment opportunity.

So why start now and incorporate commodities into your portfolio? There are two reasons that Brian O’Keefe for Forbes believes putting your money into resource markets can get you ahead.

For one, the current highs are representing a market top, but are not actually the peak, according to Jim Rogers. Even if a short-term correction were to occur, the bull market still has a long way to go.

Another reason to add commodities to your portfolio mix is that some experts suggest that they seem to offset inflation. For both of these reasons, a growing number of planners and advisors are putting 5-10% of a portfolio into commodities. It’s a new wave and some say it isn’t overly aggressive to propose a 10% allocation at this point. However, it all depends on your preference.