You’d be amazed at what you can bribe a monkey to do. One of the research groups we work with lets them watch TV to distract them. They are particularly fond of All My Children.

I’m an immunologist; we don’t do math.

Kidding, kidding, I understand, but I don’t think it’s intuitive to most people that it works like that. A lot of people think that the quoted failure rates (ie, 2% for male condoms) are the failure rates over a lifetime of use, and the graphics in the article help hammer the message home.

Also, keep in mind that the publicized control failure rates represent failure over a 1-year period, but the longer you go out, the higher the failure rate. For example, for male condoms, the failure rate of perfect use is 2% in 1 year, but 18% over a 10-year period. For typical use, it’s 18% after 1 year and a whopping 86% after 10 years. This article has interactive charts that show how the failure rates with perfect and typical use are compounded over time for several different types of birth control:

https://www.nytimes.com/interactive/2014/09/14/sunday-review/unplanned-pregnancies.html

I know that’s not exactly what you asked but I like to throw out this information because I think it’s important.