The theory says that when the 'Demis' grow in number relative to the 'Ashtons,' the stock market is about to embark upon an extended bull market. However, when the Ashtons start to outnumber the Demis, the long-term stock market trend declines.
But what matters is that there are very different types of investing behaviors that apply to different age groups: from aggressive to conservative.
"People in their 20s don't have much money, and they are busy chasing education, the opposite sex, and beer. In a country where there are a lot of guys in their 40s and very few in their 20s, there's a natural demand for equities," Kapur said in 2009 when he invented the index.
The flip side is that people in their 40s have more disposable income, relatively speaking, so they tend to invest in the stock market.
U.S. demographics applied to the Demi-Ashton theory may not bode well for equities in the long term. Baby Boomers, who were once engines of mutual fund investing, are turning 65 — an age group more commonly associated with Treasury bills and bank CDs than as active stock pickers.
For some, that conservative approach creates a hole in Kapur's theory.
"The theory sounds right," says Aneta Markowska, Senior US Economist at Societe Generale . "Where I would be a bit careful is in ignoring the older population. A growing ratio of 40-somethings to 20-somethings could indeed be positive for equities, but if the 60-somethings are growing even faster they may overwhelm the positive dynamic. That’s because people in retirement tend to sell their accumulated wealth, including equities, and therefore aging populations are generally seen as deflationary for asset prices," she adds.
Whatever the approach, this theory needs to be re-cast. Kim Kardashian and Kris Humphries? Oh, is that over? Okay... uh, Rupert Murdoch and Wendi Deng? No, no a 38 year age difference doesn't work. Mel Gibson and ... ?? Any suggestions?
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