Assets invested in money market mutual funds fell 0.9% in the week that ended June 1, to $586.14 billion, the Investment Company Institute reported.
The $5.1 billion slippage occurred across the board, in taxable and tax-exempt funds for retail and institutional investors, according to the Washington-based trade group for mutual fund companies.
Money market assets have been declining since late April, after several weeks of sharp increases earlier in the spring.
Return to Stocks Seen
Although money market balances fluctuate from week to week, the steady runoff of recent weeks suggests that investors who fled stock and bond funds earlier this year are returning to those investments.
In the week ending June 1, retail assets totaled $418.87 billion, down $2.8 billion.
Of that total, $326.46 billion was in 419 taxable retail funds, a decline of $2.3 billion.
The 251 tax-exempt funds for retail investors held $92.41 billion, down $497.3 million in the week.
Institutional funds held $167.27 billion, a $2.28 billion decline.
The 232 taxable money funds for institutional investors accounted for $145.82 billion of that figure, down $2.09 billion in the week.
The 55 tax-exempt institutional funds made up the balance of $21.45 billion, a decline of $189.9 million.