The Yom Kippur War ended in October, but the price of oil continued to increase, and by January 1974, it had quadrupled to US$12 a barrel. "The more than seven-fold increase in the oil price from $1.80/b in 1970 to $13.54/b in 1978 created profound and far-reaching changes in the world oil balance, as well as the prevailing relationships among major oil producers, principal oil importers, and the major oil companies... the spectacular jump of the crude spot price to more than $US40/b following the 1979 Iranian Revolution, turned the global oil market into total disarray." The Norwegian economics historian Ola Honningdal Grytten described that period in the 1970s as one of a prolonged global recession and slow growth that affected most developed economies.