It's worth noting that a similar decrease occurred in America after the quadrupling of oil prices in 1973-74. That oil shock led to a drive for fuel efficiency in the United States, West Europe and Japan. It also gave a boost to developing renewable sources of energy. But whereas Japan has followed a consistent, long-range policy, and reduced its petroleum usage, America has not. [...] Little wonder that the oil usage in Japan has dropped by 15% over the past dozen years.