From January 2011 through March 2018, the Bank of Japan purchased equity index exchange-traded funds (ETFs) worth about 3.5% of GDP. Identification of the effect of central bank ETF purchases on stock valuations and corporate responses is via differently-weighted and changing stock indices. BOJ purchases lift valuations, increase share issuances, and increase total assets. On average, the latter increase is due to cash and short-term securities rather than capital investment. However, firms with worse corporate governance do increase capital investment. These findings suggest central bank equity purchases are a problematic tool for stimulating economic growth through high broad-based private-sector corporate investment.

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日本银行股票购买：极端量化宽松的（非）影响

从2011年1月至2018年3月，日本银行购买了占GDP约3.5％的股票指数交易所交易基金（ETF）。通过不同加权和不断变化的股指来确定央行ETF购买对股票估值和公司响应的影响。日本央行购买股票可提升估值，增加股票发行量，并增加总资产。平均而言，后者的增加是由于现金和短期证券而不是资本投资。但是，公司治理较差的公司确实会增加资本投资。这些发现表明，中央银行购买股票是通过基础广泛的私人部门企业投资来刺激经济增长的有问题的工具。