Bubbles Forever

NEW HAVEN – You might think that we have been living in a post-bubble world since the collapse in 2006 of the biggest-ever worldwide real-estate bubble and the end of a major worldwide stock-market bubble the following year. But talk of bubbles keeps reappearing – new or continuing housing bubbles in many countries, a new global stock-market bubble, a long-term bond-market bubble in the United States and other countries, an oil-price bubble, a gold bubble, and so on.

Nevertheless, I was not expecting a bubble story when I visited Colombia last month. But, once again, people there told me about an ongoing real-estate bubble, and my driver showed me around the seaside resort town of Cartagena, pointing out, with a tone of amazement, several homes that had recently sold for millions of dollars.

The Banco de la República, Colombia’s central bank, maintains a home price index for three main cities – Bogotá, Medellín, and Cali. The index has risen 69% in real (inflation-adjusted) terms since 2004, with most of the increase coming after 2007. That rate of price growth recalls the US experience, with the S&P/Case-Shiller Ten-City Home Price Index for the US rising 131% in real terms from its bottom in 1997 to its peak in 2006.

This raises the question: just what is a speculative bubble? The Oxford English Dictionary defines a bubble as “anything fragile, unsubstantial, empty, or worthless; a deceptive show. From 17th c. onwards often applied to delusive commercial or financial schemes.” The problem is that words like “show” and “scheme” suggest a deliberate creation, rather than a widespread social phenomenon that is not directed by any impresario.