A useful metaphor for presenting information honestly is evident in how truth is defined in the American justice system by emphasizing three aspects:
- The truth: Be accurate.
- The whole truth: Be precise enough and include everything relevant.
- Nothing but the truth: Don’t be overly precise or add anything irrelevant.
Providing a measure is usually the primary dimension of the truth. Providing a credible measure with the appropriate backup context (like both the percentage and the absolute numbers) is necessary to tell the whole truth. And using accurate data with the right level of precision ensures that you are not misleading people with additional detail that obfuscates the truth. I think a statistics class should be part of every high school core curriculum. Understanding estimates, random variables, expected values, and standard deviations is crucial to many decisions and is a core skill for communicating honestly.
There is one common use of percentages that makes little sense. Has a boss or a coach asked you to give 110%? The use of numbers over 100% is silly. When someone asks you to give 110%, they are referring to your total capacity (either all your heart, all your energy, all your time, or all of something). In that context, isn’t it erroneous to request someone to give 110% of some quantity where all of that quantity is equal to 100%? Either the boss/coach is a moron (they don’t understand percentages), or the boss/coach thinks the employee/player is a moron. In my view, it is a mathematical oxymoron.