Tax-exempt money market funds lost a sizable $2.09 billion, dropping total net assets to $326.88 billion for the week ending Dec. 13 and erasing nearly all gains from the previous week, according to the Money Fund Report, a service of iMoneyNet.com.

The outflows came on the heels of $3.41 billion of inflows last week. The back-and-forth followed two consecutive weekly outflows that saw total net assets fall to $328.97 billion.

The iMoneyNet money fund average seven-day simple yield for the 481 reporting tax-free funds this week remained at 0.03%, while the average maturity remained at 32 days.

The assets of the 1,133 taxable money funds reporting this week lost an unusually large $24.64 billion, settling at $2.464 trillion for the week ending Dec. 14. That came in the wake of inflows of $29.12 billion last week, leaving assets at $2.489 trillion.

The average seven-day simple yield for taxable money funds was unchanged at 0.03%, while the average maturity remained at 48 days. 

Overall, the combined assets of the 1,614 money funds suffered outflows of $26.74 billion, finishing with $2.791 trillion in total net assets for the week ending Dec. 14. The outflow activity ate up a majority of the $32.53 billion of inflows the funds generated last week when they settled at $2.818 trillion.