Interest Rates Are An 'Unreliable Indicator'

by: Scott Sumner

I often point out that on a few occasions easy money policy announcements have actually raised long-term bond yields. But that’s obviously not always true. On the other hand persistently easy monetary policies that result in much faster trend NGDP growth do fairly consistently raise nominal rates. So why did Japanese bond yields fall on the recent moves to ease monetary policy? And why are they so low?

The second question is easy, nominal rates in Japan are low because expected NGDP growth is very low, hence the Bank of Japan has a very tight monetary policy using the Bernanke criterion. Yes, even today.

But why did rates fall on the easing of monetary policy? Because the liquidity effect outweighed the income and expected inflation effects.

Some commenters (such as Bob Murphy) seem to think I believe that nominal interest rates are a good indicator of the stance of monetary policy. That’s probably because I often quote Friedman saying that ultra-low nominal rates are a sign that money has been tight. I still believe that, but Friedman didn’t think rates were a reliable indicator of the current stance of monetary policy, and neither do I. Here’s what I wrote last year:

Consider the Fed’s options in 2003. It could have aimed for a 5% NGDP growth rate over the following three years. It actually produced a growth rate of over 6%. How would interest rates have been different if the policy generated an expected 5% NGDP growth rate? Hard to say. The slightly tighter money would have resulted in slightly higher nominal interest rates. The slightly lower expected NGDP growth would have resulted in slightly lower nominal rates. The net effect? I can’t say, I’m not even sure whether rates would have been higher or lower with slightly slower NGDP growth.

And just so you don’t think it’s an outlier, in a few minutes I dug up six other posts within the last 12 months pointing out that interest rates are not a reliable indicator of monetary policy, and I’m sure there are dozens more. (I have 1000s of posts, so it’s time-consuming to search.)

In 2013. In 2013. In 2012. In 2012. In 2012. In 2012.

That’s not to say that Japan has not caused me to rethink my estimates of various parameters. Back in 2009 I would have expected that a few years of 4% NGDP growth would have raised 10 year bond yields above 2%. I now realize that real interest rates have been on a steep downward trend for 30 years, which shows no sign of turning around. If 4% NGDP growth is consistent with 10 year bond yields under 2% in the US, then a 2% NGDP growth rate in Japan might be consistent with 10 year yields under 1%.

I think that people get confused because I emphasize the counter-intuitive; that tight money can lower interest rates, or that the fiscal multiplier may be zero. They don’t read the fine print, that in the short run tight money can raise rates via the liquidity effect, or that any estimate of the fiscal multiplier is nothing more than an estimate of central bank incompetence. (Since central banks are incompetent, fiscal multipliers need not be zero.)

I have certain core beliefs, such as the view that monetary policy drives NGDP, and that it’s silly to use fiscal stimulus when monetary policy is much less costly. Or that large and persistent increases in NGDP growth tend to raise long-term interest rates. Or that market indicators give us the best reading of the impact of monetary policy. I do not have strong beliefs on whether the fiscal multiplier is exactly zero at a particular time or place. Or whether a given change in NGDP growth will result in precisely a one-for-one change in long term bond yields. Or whether the liquidity effect will outweigh the Fisher and income effects in any particular case.

Just so that you don’t think I always cop out on past predictions, post this one on your wall:

If NGDP growth during 2013 is less than 4%, or if RGDP growth is less than 2%, then I believe fiscal austerity will have reduced growth somewhat. In other words, I believe the Fed will have failed to offset the expected fiscal austerity with its QE3 policy of late 2013.

Hold me to it.