The price of money—what we pay to borrow to buy a home, a car, or a new refrigerator—is normally set by market forces of supply and demand, just like other commodities, such as copper, sugar, gold, or crude oil. But in the aftermath of the 2008 financial crisis, which nearly wiped out the country’s most vital financial institutions in the span of six months, the Federal Reserve, the country’s central bank, decided that the normal rules of supply and demand should be temporarily suspended, at least as they apply to the cost of money. The Fed’s board of governors determined that it would be better for the deeply wounded economy if the price of money were kept artificially low for an extended period of time. That way, Fed officials figured, people and businesses that wanted to borrow money to build new facilities, or to buy new equipment or hire more employees, could do so relatively inexpensively. Taken together, the logic went, those individual acts of low-cost borrowing and investing would theoretically lift the economy out of its doldrums.

Under the direction of Ben Bernanke, the Federal Reserve’s chairman at that time, the Fed initiated a creative but not entirely unprecedented program to buy trillions of dollars worth of the mortgage and other ill-conceived securities that had been larding up the balance sheets of our major financial institutions, and that had led many of them to the precipice, and, in some cases, over it. Known alternatively as quantitative easing, or ZIRP, for zero-interest-rate policy, between 2008 and 2014 the Fed gobbled up nearly four trillion dollars worth of the securities in the market, and in the process expanded its balance sheet from having assets worth less than nine hundred billion dollars prior to 2008, to having assets worth nearly $4.5 trillion today, equivalent to the combined assets of JPMorgan Chase and Wells Fargo, the country’s largest banks.

For years, the Fed was often the only buyer in the market for these securities, which had been widely discredited as being crammed full of mortgages that should never have been approved in the first place to people who seemed unlikely to pay them off. When the Wall Street banks used these shoddy mortgage securities to finance their own operations on a short-term basis, the whole house of cards collapsed, with first Bear Stearns, and then Merrill Lynch, Lehman Brothers, and others falling into bankruptcy or nearly so. There were few buyers of these securities when the Fed started buying them in November, 2008.

The Fed’s easing policy had the intended effect of keeping interest rates unnaturally low, defying the laws of supply and demand. For years, the Fed kept buying and buying these securities, driving up their price—high demand, low supply—and driving down the cost of money, since bond prices trade in inverse proportion to their yield. (In short, the higher the price paid for a bond, the lower the effective interest rate.) And talk about low! According to an analysis by Bank of America, the price the U.S. government pays to borrow money on a long-term basis is at its lowest point, ever: the yield on the ten-year Treasury bond is 2.3 per cent; on the thirty-year bond, it’s 2.8 per cent. The yield on so-called junk bonds, the bonds of companies with less-than-stellar credit ratings—which therefore carry plenty of risk—is around 5.5 per cent. At the peak of the recent financial crisis, those yields were as much as four times higher, illustrating the risk inherent in owning the bonds of such companies. The cumulative effect of the Fed’s policy—intended or not—has been to incorrectly account for the price of risk in the market, forcing investors to take higher and higher chances in order to get the returns they desire. It has also helped to drive the stock market to record levels, as investors keep buying equities—which, by definition, are riskier than debt—in order to get the return they can no longer get on bonds. Many observers are of the view that while easing helped to jump-start the moribund economy after the financial crisis, it also has led to what is looking increasingly like a bubble in the bond and stock markets. If true, that is politically ominous for Donald Trump and his Republican allies in Congress, as a major correction in the stock or bond markets would likely slow the economy, which, fairly or unfairly, is a key arbiter of an incumbent’s popularity.

Who has benefitted from the Fed’s easing policy? The biggest beneficiary is the federal government, which, thanks to the Fed, is able to pay lower interest rates than would otherwise have been possible on its twenty trillion dollars of debt. Other major beneficiaries are people who make money from money—Wall Street banks, private-equity firms, and hedge funds among them—who can borrow money at unusually low rates and use that cheap money to buy companies, higher-yielding securities, or to make loans to others, and then take as profit the spread between the cost of the money borrowed and the cost of the money lent. Other winners are people who borrowed money to buy a home, assuming they could qualify for a mortgage. Indeed, anyone borrowing money benefitted from paying lower interest rates.

Who got burned by quantitative easing? The millions of retired Americans living on a fixed income off of the interest they receive from their bond or money-market portfolio. Lower interest rates have meant lower income for them—nearly a decade worth of lower income. Anyone with a checking or savings account has also been singed. JPMorgan Chase, for one, pays a standard 0.01-per-cent annual interest rate on both checking and savings. In other words, thanks in large part to the Fed’s easing policy, we are allowing the big banks to use our money virtually for free in return for the hope that it will still be there when we want it back.

A few years ago, in the midst of the easing, I spoke with James Grant, the publisher of the highly respected Grant’s Interest Rate Observer and a longtime Fed watcher, about the dangers of the Fed’s manipulation of interest rates. He told me then that the Fed’s vastly expanded balance sheet was “in service to an idea that the Fed ought to control and manipulate the structure of interest rates in this financial economy.” He said central bankers around the world had surrendered to the idea of “price administration”—efforts to manipulate interest rates—as opposed to “price discovery”—letting the market set the price of money, which is what interest rates are, of course. He expected the Fed’s experiment to end badly.

Now the Fed’s intervention is ending. On September 20th, Janet Yellen, Bernanke’s successor as Fed chairman, announced that the Fed would begin paring its bloated balance sheet. The announcement came in typical Fedspeak, the mystifying tendency of Fed chairmen to communicate in an argot that only the most astute Fed watchers can decipher. “In October, the Committee will initiate the balance-sheet normalization program described in the June, 2017, Addendum to the Committee’s Policy Normalization Principles and Plans,” Yellen announced. The translation? Starting next month, the Fed will reduce its balance sheet by not replacing billions of dollars of securities as they mature. Yellen’s plan, effectively, is to at first let ten billion dollars worth of bonds mature per month without being replaced and increase that amount to as much as fifty billion dollars a month, or six hundred billion dollars a year. When Yellen announced in June that she was thinking of shrinking the Fed’s balance sheet, she said she hoped its impact on bond prices and yields would be minimal. She said she hoped it would be like “watching paint dry,” repeating a phrase used by Patrick Harker, the president of the Federal Reserve Bank of Philadelphia. Yellen’s expectation is that by moving slowly, the Fed’s Great Unwind won’t increase interest rates in the same dramatic way that easing lowered them.