The 48 year Dow structure represented above provides a perspective that is proportional to numerous large and small historic examples. This 48 year structure is expected to be complete by August 30, 2019 (+/- 1 trading day), or 48 years after Nixon closed the gold window in August 1971, preventing foreign governments from exchanging their dollars for gold. Three years later the U.S. initiated the Petrodollar system.