These policies did succeed in lowering long term interest rates.

Remarkably, as short term interest rates rose, medium and long term interest rates did not, something that was referred to as a conundrum.

Moreover, low long term interest rates are a thing of the past.

An expectation that interest rates will be high sometime in the next decade should mean high interest rates on long term bonds today.

The traditional signals provided by inflation expectations, long term interest rates, and exchange rates have not started flashing.

In short, QE lowering long term interest rates by buying long term bonds and mortgages won t do much to stimulate business directly.

QE2, in which the Fed bought long term government bonds, did not have a discernible effect on long term government interest rates.

Given today s exceptionally low long term interest rates, the annual cost would be, well, peanuts.

Inflation implies higher long term interest rates until markets regain confidence in the central bank.

NEW HAVEN Real long term interest rates that is, interest rates on inflation protected bonds have fallen to historic lows in much of the world.

Investors are buying long term bonds at the current low interest rates because the interest rate on short term investments is now close to zero.

Either way, a rise in long term interest rates is liable to choke off the recovery.

But, even after disinflation in the mid 1980 s, long term interest rates remained relatively high.

So what will happen when central banks start raising interest rates? In 1994, rising short term rates caused increases in long term rates and declines in long term bond prices that were at least double what standard models at the time were predicting.

Here, monetary authorities must be vigilant, and continue their non standard interventions managing both short term and long term interest rates.

The US is not the only country with very low or negative real long term interest rates.

It also lowered long term interest rates in the US and made monetary conditions there more expansionary.

Given modest inflationary pressures, long term real interest rates rose but nevertheless remained close to historical lows.

The Federal Reserve is of a similar mind, not only maintaining rock bottom short term interest rates, but also embarking on an adventurous policy targeting long term rates.

Within a couple years, interest rates on long term US Treasury notes could easily rise 3 4 , with interest rates on other governments paper rising as much, or more.

Yet financial markets are not pricing dollar depreciation and a rise in long term US interest rates accordingly.

The resulting increase in real long term interest rates will reduce all forms of interest sensitive spending, adding further to the economy s weakness.

If it falls 40 against the yen sometime in the next ten years, US long term interest rates should be four percentage points higher than Japanese rates. If it falls 60 against China s currency, the yuan, sometime in the next ten years, US long term interest rates should be six percentage points higher than Chinese rates.

CAMBRIDGE Long term interest rates are now unsustainably low, implying bubbles in the prices of bonds and other securities.

The Fed has pursued its strategy of low long term interest rates in the hope of stimulating economic activity.

But not now given extraordinarily low long term interest rates, no serious economist raises the crowding out issue nowadays.

But, even with that decline, many countries long term interest rates will most likely remain higher than their growth rates for the next several years.

The Long Mystery of Low Interest Rates

In this case, the price of loanable funds is the real interest rate. An expectation that interest rates will be high sometime in the next decade should mean high interest rates on long term bonds today.

One oft heard justification for high asset prices is that real (inflation adjusted) long term interest rates are very low.

Moreover, ECB chief economist Otmar Issing predicts long term interest rates would go up not down as inflationary expectations increased.

Ordinarily, rapid global growth translates into high long term interest rates that is, unless, deep down, people have become nervous.

The hope is that if investors consider this announcement credible, long term interest rates will come down further, encouraging spending.

Moreover, ECB chief economist Otmar Issing predicts long term interest rates would go up not down as inflationary expectations increased. So cutting interest rates would not only be stupid it would be crazy.

First, while the US Federal Reserve continued hiking short term interest rates, long terms rates did not increase in tandem, which allowed housing prices to continue rising.

Or, if these deficits are monetized, high inflation may force up long term interest rates and again choke off economic recovery.

A second argument is that higher oil prices are due to lower interest rates and anticipations of higher long term prices.

But, while bank profitability and bonuses have returned, lending has not recovered, despite record low long and short term interest rates.

The Fed cannot reduce short term interest rates below zero, so it is attempting via this policy of quantitative easing to reduce longer term interest rates.

Investors are buying long term bonds at the current low interest rates because the interest rate on short term investments is now close to zero. In other words, buyers are getting an additional 2 current yield in exchange for assuming the risk of holding long term bonds.

A great puzzle in today s world economy is the continued low level of long term real interest rates in the United States.

On the contrary, they are puzzled about why we view the current low level of US long term interest rates as worrisome.

In short, we simply shouldn t read too much into the decline in real long term interest rates over the last 20 years.

In normal times, any effort by a central bank to take short term interest rates too low for too long will boomerang.

Clearly, the Fed s objective is to increase bond prices, in the hope that lower long term interest rates will propel corporate investment.