These past few months have seen several booms becoming busts—equities, derivatives, housing and oil. The plunge in each of these markets has been steep enough for sceptics to ask disturbing questions: Were the past 20 years normal or abnormal? Or are these times the normal state of affairs?
It is hard to tell, unless you believe in the theory that economies and markets move in long waves, with many decades of good years inevitably followed by many decades of bad years.
But what is more disturbing is when similar questions are asked about the recent collapse in world trade, which followed a 20-year boom when the ratio of trade to global output soared and helped pull millions in countries such as India and China out of poverty.
The recent trade numbers have been dismal: The latest data shows that Chinese exports are down 17% from a year ago while imports have plunged 43%. The US, too, has seen its trade with the rest of the world fall off a cliff. Is this the end of a trade bubble? We hope not.