The following exercise took one minute and 19 seconds.

Step One: I went to Vanguard’s website at vanguard.com.

Step Two: I went to a listing of all Vanguard’s funds, organized by fund type.

Step Three: I scrolled down to the list of intermediate-term bond funds.

Step Four: I noted that the Vanguard Intermediate Term Bond Index Fund had a current yield of 4.57%, while the Vanguard Intermediate-Term Tax-Exempt Fund had a current yield of 3.2%.

Step Five: I look at the tax tables to see what tax bracket I’m in. Since I’m a joint filer and my taxable income is slightly more than $114,650, but woefully less than $174,700, I’m in the 30% tax bracket. I multiplied 4.57% by .7. The answer: 3.199%.

Wow! Who’d a thunk it? The after-tax return of these two funds is virtually identical. So if I’m investing in the Vanguard Intermediate Term Bond Index Fund, there’s no reason to switch because I won’t come out ahead after taxes. But it doesn’t hurt to check every now and then, especially since it took me less than 90 seconds to do it. Now I can move on with confidence.

Another tax-advantaged source of interest is the money you collect in tax-deferred accounts. Prime example of this type of account? Your 401(k,) IRA or other retirement account. You don’t report money you make in these accounts. While you will pay taxes on any money you withdraw, investing in these types of accounts is cool because you don’t pay the taxes now, nor do you deal with any time-consuming paperwork reporting interest you receive or profits you make. That’s why we like these types of accounts. Yes, we’ll have to pay taxes in the long run. But in the long term we’re all dead.