Pro tip: With a history of 9 passwords, change your password 10 times every time you change it until you loop back to the original. That way you can use the same password indefinitely.
I thought of that, but we have a really bad AD/Mac setup where changing your password takes 30-60 minutes to propagate. During the time you try both your old and new passwords until they work.
If you try to change it again during the 30-60 minutes propagation time, then you need to try even more passwords passwords. Too complex to deal with.