国际油价波动的周期模型及其政策含义

The cyclical model of international oil price fluctuations and its policy implications

第二次世界大战以来,世界石油市场经历了三次大的油价波动周期,目前国际油价处于高油价周期当中。用多重均衡模型对油价波动的周期进行解释,油价波动的原因来自于供给曲线的特殊性和多重均衡的存在。多重均衡模型的最大用处在于可以对油价均衡拐点提前作出判断。高油价均衡向低油价均衡转化需要具备两个条件:1)需求受到明显抑制,增长幅度下降;2)产量增长幅度开始超过需求增长幅度。低油价周期向高油价周期转化的拐点条件则相反。遏制国际油价暴涨要么增加供给(及其幅度),要么减少需求(及其幅度)。本轮高油价周期向低油价周期转换的拐点可能发生在:1)世界经济总体放缓;2)全球应对气候变化已经从一种政治思潮落实到各国行动上。未来的油价走势充满不确定性,但做出判断好过不做任何判断。

Since the Second World War, the global oil market has experienced three major cycles of price volatility, and it is currently in the midst of a high price cycle. Under the multiple equilibrium model of oil price fluctuation cycles, fluctuations in price are caused by the peculiarities of the supply curve and by the existence of multiple equilibria. The key to the multiple equilibrium model lies in determining the inflection point for oil prices. For high oil prices to fall, two conditions are required: 1) Clear restraints on demand and a falling growth rate; 2) Growth in production begins to exceed growth in demand. The conditions required to shift from a low to a high oil price cycle are exactly opposite. Skyrocketing oil prices may be controlled by increasing supply (and amplitude), or by reducing demand (and amplitude). The inflection point which will shift the current high cycle to a low cycle may occur when: 1) There is an overall slowdown in the world economy; 2) Global measures against climate change are translated from a political trend into national action. The future of oil prices is fraught with uncertainty, but it is better to make some judgment than none at all.