Basically what they are offering is a return on your money that is relatively safe and liquid, meaning you can convert it to cash quickly and easily. The yeild is on a per year basis, meaning you will receive about 2% on your investment per year. the reason why the california tax exempt fund is only 1.4 % is because it is tax exempt, while you will be taxed on the 2% or so you earn on the others. These really are low returns for your money. Most b&m banks offer low returns on what is basically a savings account. in comparison, i put my money in an ing account that earns about 4%, (it was 6) and only keep what i will need for the month in my wellsfargo checking.