Another way of exploring the numbers is whether they are naked numbers; in other words does the speaker include the referent with the number. A naked number is one that has no referent attached such as "two-ninety nine" for a price or "six two" when referring to someone's height. This activity can be amped up considerably by pretending one is from another country, planet or occupation. For example a "two point five" would not cause any alarm if it came up in a discussion about engine size. When discussing student GPAs, however, it can have the most dire consequences for someone.
It would be interesting to develop NMPs for different groups of people. For example, would an NMP for a group of mathematicians be different from an ensemble of historians at their monthly department meetings? What would the NMP be for a group of 20-somethings out for the night on the town?