Ever since markets crashed in 2008, investors have been slowly increasing their risk appetites, shifting towards more lucrative and risky asset classes such as commodities. Some investments in this category have flourished, while others haven’t fared so well. Natural gas is perhaps the first cringe-worthy commodity that comes to mind as investors witnessed its unprecedented free fall over the last few years. But with NG and some of the other big losers comes a potential buy in opportunity at rock bottom prices. Whether you’re looking for a bargain or simply want to avoid these bad-performing funds, we outline 3 of the worst performing commodity ETPs over the last three years. Note that this list is a bit modified in that we only chose one fund from each commodity type [see also 12 High-Yielding Commodities For 2012].