Abstract In April 2013, the Bank of Japan (BOJ) introduced an inflation target of 2% with the aim of overcoming deflation and achieving sustainable economic growth. But due to lower international oil prices it was unable to achieve this target and was forced to take further measures. Hence, in February 2016, the BOJ adopted a negative interest rate policy by massively increasing the money supply through the purchase of long-term Japanese government bonds (JGB). The BOJ had previously only purchased short-term government bonds, a policy that flattened the yield curve of JGBs. On the one hand, banks reduced the number of government bonds they purchased because short-term bond yields had become negative. The interest rates of long-term government bond up to 15 years even became negative. On the other hand, bank loans to corporates did not increase, due to Japanese economy’s vertical investment–saving (IS) curve. The purpose of this paper is to show that the monetary policy through implementation of the zero interest rate and more recently through the negative interest rate could not help the Japanese economy to recover from the long-lasting recession and these are not the remedy. It is of key importance to make the IS curve downward rather than vertical. That means the rate of return on investment must be positive and companies must be willing to invest even if interest rates are set too low. Japan’s long-term recession is due to structural problems that cannot be solved by its current monetary policy. The paper also explains why the BOJ has to reduce its 2% inflation target in the present low oil price era.

中文翻译：

---

日本的油价下跌和负利率政策

摘要2013年4月，日本银行（BOJ）提出了2％的通胀目标，以克服通货紧缩并实现可持续的经济增长。但是由于国际油价下跌，它无法实现这一目标，因此被迫采取进一步措施。因此，日本央行在2016年2月采取了负利率政策，通过购买长期日本国债（JGB）大量增加了货币供应量。日本央行此前只购买了短期政府债券，这一政策使日本国债的收益率曲线趋于平坦。一方面，银行减少了购买的政府债券的数量，因为短期债券收益率已经为负。长达15年的长期政府债券利率甚至变为负数。另一方面，向企业的银行贷款没有增加，由于日本经济的垂直投资-储蓄（IS）曲线。本文的目的是表明，通过实施零利率以及最近通过负利率实施的货币政策无法帮助日本经济从长期衰退中恢复过来，而这并不是补救措施。使IS曲线向下而不是垂直是至关重要的。这意味着投资回报率必须为正，即使利率设置过低，公司也必须愿意进行投资。日本的长期衰退是由于结构性问题而无法通过其当前的货币政策解决的。本文还解释了为什么在当前低油价时代，日本央行必须降低其2％的通胀目标。本文的目的是表明，通过实施零利率以及最近通过负利率实施的货币政策无法帮助日本经济从长期衰退中恢复过来，而这并不是补救措施。使IS曲线向下而不是垂直是至关重要的。这意味着投资回报率必须为正，即使利率设置过低，公司也必须愿意进行投资。日本的长期衰退是由于结构性问题而无法通过其当前的货币政策解决的。本文还解释了为什么在当前低油价时代，日本央行必须降低其2％的通胀目标。本文的目的是表明，通过实施零利率以及最近通过负利率实施的货币政策无法帮助日本经济从长期衰退中恢复过来，而这并不是补救措施。使IS曲线向下而不是垂直是至关重要的。这意味着投资回报率必须为正，即使利率设置过低，公司也必须愿意进行投资。日本的长期衰退是由于结构性问题而无法通过其当前的货币政策解决的。本文还解释了为什么在当前低油价时代，日本央行必须降低其2％的通胀目标。