Productivity growth, however it occurs, has a disruptive side to it. In the short term, most things that contribute to productivity growth are very painful.

In 1977, when I started my first job at the Federal Reserve Board as a staff economist in the Division of International Finance, it was an article of faith in central banking that secrecy about monetary policy decisions was the best policy: Central banks, as a rule, did not discuss these decisions, let alone their future policy intentions.

The distribution of wealth is even more unequal than that of income. ...The wealthiest 5% of American households held 54% of all wealth reported in the 1989 survey. Their share rose to 61% in 2010 and reached 63% in 2013. By contrast, the rest of those in the top half of the wealth distribution —families that in 2013 had a net worth between $81,000 and $1.9 million —held 43% of wealth in 1989 and only 36% in 2013.

I think it is appropriate to ask whether this trend is compatible with values rooted in our nation's history, among them the high value Americans have traditionally placed on equality of opportunity.

For my own part, I did not see and did not appreciate what the risks were with securitization, the credit ratings agencies, the shadow banking system, the S.I.V.’s — I didn’t see any of that coming until it happened.

We need to increase the transparency of shadow banking markets so that authorities can monitor for signs of excessive leverage and unstable maturity transformation outside regulated banks.

After adjusting for inflation, the average income of the top 5% of households grew by 38% from 1989 to 2013. …By comparison, the average real income of the other 95% of households grew less than 10%.