How many years of commentary and interpretation are contained in an ancient compendium of divination, which dates back to at least 672 BCE?
Chinese philosophy:  Although much of Chinese philosophy begins in the Warring States period, elements of Chinese philosophy have existed for several thousand years; some can be found in the Yi Jing (the "Book of Changes"), an ancient compendium of divination, which dates back to at least 672 BCE. I Ching:  Possessing a history of more than two and a half millennia of commentary and interpretation, the "I Ching" is an influential text read throughout the world, providing inspiration to the worlds of religion, psychoanalysis, business, literature, and art.
two and a half millennia