Despite the economic uncertainty caused by the pandemic—or possibly because of it—US retirement account balances rose to record levels during the fourth quarter of 2020, as reported by Fidelity Investments. The firm said individual contributions to individual retirement accounts (IRA), as well as 401(k) and 403(b) retirement accounts remained strong during the last three months of the year.
For decades, financial risk modeling has been based on standard deviation assumptions, such as the Gaussian Distribution, modern portfolio theory, and bell curve risk models. While this approach works great in fields like science, it has shown significant shortcomings during extreme market events. Why?
just 10 stocks are currently responsible for around 80% of market movement, pushing the index to its highest concentration levels in 50 years. The conversation explains how the S&P 500's market-cap weighting amplifies this effect, making the index less diversified than it appears.