Boosted by surging global stock prices, the assets in ETFs topped $697.99 billion at the end of September. Assets grew by $32 billion from the previous month.

The largest ETF categories by assets are U.S. equities ($329.74 billion), global international equities ($177.53 billion), fixed income ($90.47 billion).

Currently, there are 785 U.S. listed ETFs and 83 ETNs. The number of new issues has grown by 42 over the past year.

In a research report, State Street Global Advisors notes, “Despite the impressive growth of dollars invested in ETFs it’s still only about 5.8 percent of the total of $10.43 billion the U.S. traditional mutual fund industry at the end of August 2009.”

The ETF industry is already beginning to eye the coveted 401(k) business, a place where mutual funds have long dominated. This is viewed by many as the next progression for ETFs and will help the business to continue its growth.