As you read this, you are likely aware of what time it is, how old you are, your checking account balance, your weight, and so on.

Clerk: we mean that we compute interest on your account balance every day and credit it to your account on a quarterly basis.

Think tank RAND calculates that even just 1 percentage point difference in annual fees adds up to $3, 380 after 10 years on a $20, 000 account balance.