Now, i´m just a second stage (i´m learning to become a datanome, in profession school [ok, it´s not high school, but the place where you go study a real job, and it´s a school of the same level, after comprehensive school i think...] god, i´m bad with words...) but even i think you´d need to know more than that he cleared six meters.
I think what you´d at least need is:
How high is he in the air, how heavy is he, is he tall or short (affects somewhat the location of his center of gravity), and how fast was he going when he pole vaulted. (his starting speed...)