The decline escalated fears over the safety of money funds and inflamed the crisis. The next week, investors pulled around $300 billion from so-called "prime" money funds, representing 14 percent of the assets in those funds. Short-term lending, relied on by companies to pay suppliers and make payroll, froze up as investors abandoned the funds. The Fed stepped in to temporarily guarantee assets of all money funds so investors could be assured that they would be protected from losses.
The new floating-price requirement applies only to prime institutional funds, which are considered riskier. They represent about 35 percent of money-market funds, according to the Investment Company Institute, the fund industry's trade group. Those funds attract mainly big institutional investors and are considered more risk-prone because they invest in short-term corporate debt.
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The industry has lobbied against the requirement for floating share prices, saying it would make money funds unattractive.
Verett Mims, the assistant treasurer at Boeing, said the aircraft maker usually has about $2 billion to $3 billion in money-market funds, mostly in prime institutional funds. They offer Boeing the best quick access to cash and flexibility while preserving principal, Mims said in a conference call Tuesday organized by the U.S. Chamber of Commerce.
The cost and complexity of floating fund prices are "not worth it," she said, and Boeing likely would have to move money out of the funds under the SEC changes.