I'm not so sure that wisdom can be measured.
Often I don't even realize that I possess any wisdom in regards to a given topic until I'm called upon, or put in a position to display it.
Much of what is thought to be some form of mysterious wisdom, is in fact just a recognition of patterns. The longer we live, the more patterns we notice developing. For instance....I can tell, without looking up, whether the person pulling into my place is a buddy, a longtime customer, or someone who is stopping by for the very first time....just by the sound of the gravel under their tires. That's "wisdom". Spawned only by experience and the level in which a person pays attention and processes information.