He isolated each factor in a separate chart, calling them “eras” for the stock market.
From after World War II until the mid-1970s, future GDP outlook explained 90% of the stock market’s move, according to statistical analysis by Barnier.
GDP growth lost its sway on the market in the early 1970s with the rise of credit cards and consumer debt. Household liabilities grew with plastic first, followed by home mortgages, until the real estate crash of the early 1990s. Barnier’s analysis shows debt explained 95% of the entire market’s move during this time.
The period between the mid- to late-1990s until 2000 was, of course, marked by the tech bubble. While stocks took much of the headline, that time also saw heightened activity in the commercial paper market. Startups and young companies sought cash beyond their stratospheric share values to fund their operations. Barnier’s regression analysis shows commercial paper increases could explain as much as 97% of the tech bubble.
Shortly after the tech bubble burst, a housing bubble began, once more in the form of mortgages and other debt. That drove 94% of the market’s move for the first several years of the current century.