Vanguard Money Market down

I’m doing my son’s taxes and I noticed a big drop in his interest on his money market account. The first part of 2020 was making about 200.00 a month. In December of 2020, he was making about 2.50 a month. Sound right?

Quite possible. I noted similar drops in my bank’s MM as well as my Fidelity core accounts.

It probably costs the bank more to calculate and post the interest amounts to accounts than the amounts posted.

Seconded. My interest yields dropped yugely.