本稿では, 物価水準の財政理論(The fiscal theory of the price level : FTPL)の含意と, わが国における妥当性を考察する。FTPLに基づくと, デフレ脱却のために政府債務の返済を先送りすると, 目下のデフレを深刻化させることや, 国債の発行と償還を変えずに現在のマネタリーベースだけを増やすと, 現在の物価水準は低下することを明らかにした。さらに, そもそもわが国でFTPLは成り立つのかという問いもある。わが国の財政・金融政策の運営スタンスを, マルコフスイッチングモデルを用い検証すると, 第2次安倍内閣以降では, FTPLが想定する前提が成り立っていないことがわかった。わが国ではFTPLを前提とした議論は, 目下妥当ではないといえる。
This paper investigates the implications of the fiscal theory of the price level (FTPL) and its applicability to Japan's fiscal situation. In Japan, since the beginning of 2017, discussions about fiscal and monetary policy based on the FTPL have been somewhat misleading. We find that under the FTPL, when the government postpones the redemption of government bonds to reduce the current fiscal burden and stop deflation, the price level further decreases. Furthermore, under the FTPL, the current price level may decline only when the current monetary base increases without changes in the schedule of issuance and redemption of government bonds.
There is thus a fundamental question here : Does the FTPL hold water in Japan? The FTPL holds water when the fiscal policy is non-Ricardian and monetary policy is "passive" (the interest rate does not react sufficiently to the inflation rate). We examine the position of the fiscal and monetary policies using a Markov switching model. From the results, we find that Japan's monetary policy is passive but its fiscal policy is not non-Ricardian after 2013 (the second Abe administration). This means that the FTPL does not hold water for this period, and policy discussions based on the FTPL are not valid.

特集 : 財政危機と金融危機のコンテイジョンと危機管理対応