Question: When did the current central bank of the country that conducted the Castle Bravo test start quantitative easing?

<P0-S0> beginning in march 2009, the bank of england had purchased around £165 billion in assets as of september 2009 and around £175 billion in assets by the end of october 2009. at its meeting in november 2009, the monetary policy committee (mpc) voted to increase total asset purchases to £200 billion. <P0-S1> most of the assets purchased have been uk government securities (gilts); the bank has also purchased smaller quantities of high - quality private - sector assets. <P0-S2> in december 2010, mpc member adam posen called for a £50 billion expansion of the bank's quantitative easing programme, while his colleague andrew sentance has called for an increase in interest rates due to inflation being above the target rate of 2%. <P0-S3> in october 2011, the bank of england announced that it would undertake another round of qe, creating an additional £75 billion. <P0-S4> in february 2012 it announced an additional £50 billion. <P0-S5> in july 2012 it announced another £50 billion, bringing the total amount to £375 billion. <P0-S6> the bank has said that it will not buy more than 70% of any issue of government debt. <P0-S7> this means that at least 30% of any issue of government debt will have to be purchased and held by institutions other than the bank of england. <P0-S8> in 2012 the bank estimated that quantitative easing had benefited households differentially according to the assets they hold; richer households have more assets. <SEP> <P1-S0> The picture below shows the Shrimp device, detonated on March 1, 1954 at Bikini, as the Castle Bravo test. <P1-S1> Its 15-megaton explosion was the largest ever by the United States. <P1-S2> The silhouette of a man is shown for scale. <P1-S3> The device is supported from below, at the ends. <P1-S4> The pipes going into the shot cab ceiling, which appear to be supports, are actually diagnostic light pipes. <P1-S5> The eight pipes at the right end (1) sent information about the detonation of the primary. <P1-S6> Two in the middle (2) marked the time when x-radiation from the primary reached the radiation channel around the secondary. <P1-S7> The last two pipes (3) noted the time radiation reached the far end of the radiation channel, the difference between (2) and (3) being the radiation transit time for the channel. <SEP> <P2-S0> The Federal Reserve System (also known as the Federal Reserve or simply the Fed) is the central banking system of the United States. <P2-S1> It was created on December 23, 1913, with the enactment of the Federal Reserve Act, after a series of financial panics (particularly the panic of 1907) led to the desire for central control of the monetary system in order to alleviate financial crises. <P2-S2> Over the years, events such as the Great Depression in the 1930s and the Great Recession during the 2000s have led to the expansion of the roles and responsibilities of the Federal Reserve System. <SEP> <P3-S0> The US Federal Reserve belatedly implemented policies similar to the current quantitative easing during the Great Depression of the 1930s. <P3-S1> Specifically, banks' excess reserves exceeded 6 percent in 1940, whereas they vanished during the entire postwar period until 2008. <P3-S2> Despite this fact, many commentators called the scope of the Federal Reserve quantitative easing program after the 2008 crisis ``unprecedented ''. <SEP> <P4-S0> government involvement in the british economy is primarily exercised by her majesty's treasury, headed by the chancellor of the exchequer, and the department for business, energy and industrial strategy. <P4-S1> since 1979 management of the economy has followed a broadly laissez - faire approach. <P4-S2> the bank of england is the uk's central bank and its monetary policy committee is responsible for setting interest rates, quantitative easing, and forward guidance.