中文摘要：

本文采用波动因素时点分解方法,选择国际原油市场的供给、需求等指标,对2014-2015年与2008-2009年国际油价的下跌因素进行月度分析。研究发现：世界经济增速放缓是2014-2015年油价持续下跌的主因。OPEC的原油不减产决定、国际金融市场的预期逆转共同导致油价在2015年进一步下跌。而2008-2009年油价的短暂下跌主要是由投机基金的撤离、发达经济体遭受全球金融危机后原油需求减少所导致。政策层面预示着我国在关注原油需求萎缩的同时,须及时评估供给侧因素,并采取合理措施。

英文摘要：

The time point decomposition methods of fluctuation factors was used to study the supply, demand and related economic indicators in the international crude oil market, and the impact factors of oil price slumps was analyzed monthly in two periods, namely 2014-2015 and 2008-2009. The study shows that： the world economy slowdown was the main reason for oil price slumps in 2014-2015. The no cut pledge by OPEC and the reversed expectation in the international financial markets have resulted in the further going down of oil prices in 2015. Comparatively, the oil price slumps of 2008-2009 was driven jointly by the decreased demand of advanced economies originated from global financial crisis and the withdrawal of speculative funds of the international financial markets. Hence, the policymaking should emphasize both demand and supply elements, and take reasonable measures.