Money market funds seem to be defying gravity. They are paying less in interest to investors, but becoming more popular.

Given a choice, people usually want more for their money, not less. Yet since the Federal Reserve began pushing short-term interest rates down more than a year ago, investors have been funneling hundreds of billions of additional dollars into these funds.

That may seem strange but there are good reasons for it. Thanks to a combination of convenience, good returns, and favorable comparisons with alternatives, money market funds are likely to continue attracting enormous wads of cash, even though the Fed announced on Wednesday that it was lowering short-term interest rates by a quarter of a percentage point.

Big money market funds have been paying more than 4 percent annualized interest, according to Crane Data, an independent financial market research firm. Within the next several weeks, these funds are almost certain to offer about a quarter of a percentage point less. But Peter G. Crane, a founder of Crane Data, is quite confident that their appeal will be undiminished.

“I expect about $100 billion to pour into money market funds each month for the rest of the year,” he said in an interview. “The funds will probably reach $8 trillion in assets by the end of this calender year,” up from around $7.8 trillion now, he said. “That’s very likely to happen, even though rates are going lower.”

Why the continuing popularity?

Basically, it’s because money market funds are still a good deal, even if they are no longer paying more than 5 percent interest, as many of the biggest funds did through much of last year.