Both ASO and GRN command very little trading volume, but investors should not expect to see GRN disappearing anytime soon. The iPath line of ETNs spawned from the same family as the highly popular iShares line. iShares has long been home to popular products such as iShares S&P 500 Index ( IVV) and iShares Russell Midcap Index ( IWR), which pay for themselves and their less-successful peers.

While the closing of ETFs may be a pain for shareholders, the Darwinian result has helped take poor performing products off the market. Upstart ETF issuers have to be lean and mean, delivering products that customers want and taking aim at ETF standards offered by other fund groups.

The industry is experiencing a fundamental shift, however, highlighted by the recent BlackRock ( BLK) acquisition of iShares. The players at the top of the ETF industry are getting bigger and asset managers like Schwab ( SCHW) will soon be offering their own line of products. Here's to hoping that consumers will continue to demand excellence and that the viability of funds will keep the ETF universe from becoming bloated.
At the time of publication, Dion had no positions in the stocks mentioned.

Don Dion is the publisher of the Fidelity Independent Adviser family of newsletters, which provides to a broad range of investors his commentary on the financial markets, with a specific emphasis on mutual funds and exchange-traded funds. With more than 100,000 subscribers in the U.S. and 29 other countries, Fidelity Independent Adviser publishes six monthly newsletters and three weekly newsletters. Its flagship publication, Fidelity Independent Adviser, has been published monthly for 11 years and reaches 40,000 subscribers.

Dion is also president and founder of Dion Money Management, a fee-based investment advisory firm to affluent individuals, families and nonprofit organizations, where he is responsible for setting investment policy, creating custom portfolios and overseeing the performance of client accounts. Founded in 1996 and based in Williamstown, Mass., Dion Money Management manages assets for clients in 49 states and 11 countries. Dion is a licensed attorney in Massachusetts and Maine and has more than 25 years' experience working in the financial markets, having founded and run two publicly traded companies before establishing Dion Money Management.

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