Diversification Is Key and the Only Free Lunch in These Markets

As both traditional and alternative asset markets descend into turmoil this month, it’s important to remember the inherent strengths of a diversified portfolio. A market rout always causes correlation to go to 1 across virtually all assets as investors flee to the perceived safety of cash. This can give rise to unfounded narratives based on extremely narrow datasets as investors panic and question sound investment principles. The market always comes back.

These short-term correlations are not as important to portfolio structure as studying the way an asset reacts across a range of economic environments. For that reason, we’ve isolated our research on each market period. First, we explore the nature of historical correlations between cryptocurrencies and traditional assets, preceding the recent panic. Later on, we will dissect bitcoin’s behavior during the recent flight to safety.

Executive Summary

  • Bitcoin has historically achieved nearly zero correlation with the US dollar and with US equities, EM equities, and the oil markets.
  • On a risk-adjusted basis, a more diversified portfolio is more efficient.
  • Bitcoin and stocks have different responses to changes in economic environments, which drives the volatile correlations observed.
  • High correlation in a black swan doesn’t invalidate the benefits of diversification in every other situation, including (and in particular) sector-specific crises.
  • The pattern of Bitcoin’s returns thus far should make any portfolio manager pause to consider the truly diversified source of risk it provides in a well-constructed portfolio.

Priming the Pump: Correlation as a Tool

To begin at the beginning, adding low correlation assets to any portfolio will improve its risk profile. While the portfolio’s expected return will change commensurately, we evaluate portfolio performance on a risk-adjusted basis, and so we can produce any desired expected return from a portfolio of sufficient Sharpe ratio by merely adding in some leverage.

Portfolio Expected Volatility Decreases as 0% Correlation Assets are Added

Note the mechanism by which diversification reduces risk - even if you had assets all with the same expected volatility, low correlation means that as one asset swings into a downturn, the other has no reason to follow it down, and so returns are smoothed out.

Cumulative Returns of Concentrated and Diversified Portfolios, 2000-2019

The above chart gives a sense of how diversification has performed through time, allowing for the fact that 2000-2019 is a peculiar and short time scale over which to observe gains.