Report Industry Investment Rating - Not provided in the given content Core View - Similar to the Bank of Japan, the Fed's bond - buying policy was initially a tool for liquidity adjustment. In 2008, the sub - prime mortgage crisis led to systemic financial risks and exhausted traditional interest - rate cut space, prompting the Fed to turn to QE. In 2020, the COVID - 19 outbreak restarted QE. In the short term, the impact of the QE policy on Treasury yields evolves more through investors' expectations, while in the long term, the US QE significantly affects long - term Treasury yields. Large - scale bond purchases provide liquidity to the financial market and drive down interest rates to some extent [1][66]. Summary by Different Stages First Stage (Before 2008): Traditional Monetary Policy Tool for Providing Liquidity - **Macro Background and Policy Objectives**: To meet the continuous expansionary demand for base money, the Fed used open - market operations (permanent and temporary) to control the money supply and influence interest rates. Asset purchases mainly supported currency issuance, while repurchase transactions smoothed liquidity disturbances [14][15]. - **Bond - buying Method**: One - way purchases in the primary and secondary markets. The Fed usually conducted weekly bond - buying operations in the secondary market through the SOMA. From 2004 - 2006, it carried out 40, 24, and 39 cash - bond transactions respectively, with average single - time increases of $1.28 billion, $1.04 billion, and $0.92 billion [20]. - **Impact on the Bond Market**: The Fed's bond - buying had a relatively limited impact on the bond market as its core goal was to limit the impact on normal market functions and the purchase scale was generally small. US Treasury yields were mainly determined by market expectations of future economic growth, inflation, and policy rates [38]. Second Stage (2008 - 2014): Quantitative Easing after the Sub - prime Mortgage Crisis - **Macro Background and Policy Objectives**: The 2008 sub - prime mortgage crisis led to a liquidity crisis. The Fed implemented QE to stabilize the financial and real - estate markets, lower long - term interest rates, and stimulate the economy by purchasing assets and expanding its balance sheet [39][40]. - **Bond - buying Method**: Continuous purchases in the secondary market. The QE process included three rounds and a twist operation. QE1 (2008.11 - 2010.3) had a total scale of $1.725 trillion; QE2 (2010.11 - 2011.6) involved buying $600 billion of long - term Treasuries; the twist operation (2011.9 - 2012.12) sold short - term Treasuries and bought an equal amount of long - term Treasuries; QE3 (2012.9 - 2014.10) was an open - ended plan. The Fed started tapering in 2013 [41][44]. - **Impact on the Bond Market**: The actual bond - buying operations had inconsistent effects on bond yields. After the QE policy was introduced, the bond market traded more based on investors' expectations. In the long run, the QE policy significantly reduced US bond yields. From October 2008 to October 2014, the yields of 1 - year and 10 - year Treasuries dropped by 124BP and 166BP respectively [47][48]. Third Stage (2015 - 2018): Difficult Exploration of Normalization - **Macro Background and Policy Objectives**: With the US economy's moderate recovery, the Fed aimed to exit the ultra - loose policy through passive balance - sheet reduction to avoid asset price bubbles and financial risks [49][50]. - **Bond - buying Method**: No reinvestment after bond maturity. The Fed raised interest rates 9 times from the end of 2015 to the end of 2018 and started QT in October 2017, gradually reducing its bond holdings [51][52]. - **Impact on the Bond Market**: After the QT policy was implemented, US Treasury yields continued to rise. It is believed that balance - sheet reduction increased Treasury yields as it meant less demand for US Treasuries and occurred during the late stage of the interest - rate hike cycle [55]. Fourth Stage (2019 - 2022): Unprecedented Response to the Pandemic - **Macro Background and Policy Objectives**: The COVID - 19 outbreak in 2020 led to an economic slowdown and market panic. The Fed launched an "unlimited QE" to start the crisis - response mode [56][57]. - **Bond - buying Method**: Unlimited QE - Taper - Balance - sheet reduction. The Fed cut interest rates to zero in March 2020, launched a $700 billion QE plan, and then an "unlimited QE". It started tapering in November 2021 and planned to end QE in mid - 2022. Balance - sheet reduction started in May 2022 [58][60][61]. - **Impact on the Bond Market**: After the "unlimited QE" was announced, US bond yields declined. However, due to factors such as investors' expectations and economic fluctuations, the ultimate impact of the Fed's bond - buying was limited. In 2022, the Fed's bond - buying failed to lower bond yields [63][65].