What Would a 10% Bitcoin Portfolio Have Returned Since 2015?

The Setup

Start with a standard 60/40 portfolio: 60% US stocks (SPY), 40% US aggregate bonds (AGG). Now carve out 10% for Bitcoin, taken proportionally: 54% stocks, 36% bonds, 10% Bitcoin. Invest $10,000 at the first available weekly close in January 2015. Rebalance once a year. Wait.

The “without Bitcoin” portfolio is the plain 60/40, on the same start date, same rebalancing, same $10,000. SPY and AGG use dividend- and split-adjusted weekly prices. Bitcoin uses the latest weekly close on or before each stock observation. These are completed-week price proxies; fees, taxes and execution costs are excluded.

Growth of $10,000

The chart shows both portfolios from January 2015 to the most recent week in our data. The outcome depends on this start date, allocation and annual rebalancing rule.

Volatility uses weekly sample standard deviation, annualised by the square root of 52. Sharpe uses the arithmetic mean and sample standard deviation of weekly returns above BIL, a 1 to 3 month US Treasury-bill ETF, on matching dates, with the same annualisation. BIL adjusted closes include dividends and fund expenses. It is a cash proxy, and the annualisation assumes no serial correlation. An unavailable ratio is shown as n/a.

What the Numbers Say

A 10% Bitcoin allocation would have meaningfully improved returns without the kind of volatility increase you might expect. The Sharpe ratio, return per unit of risk, tells the story: you got paid for the extra risk.

Max drawdown was larger with Bitcoin, which is the tradeoff. During the 2022 crash, the Bitcoin-enhanced portfolio fell further and took longer to recover. Bitcoin has experienced 16 drawdowns over 20% since 2010. All the completed ones recovered to new highs, and the rides down were brutal. Whether that tradeoff is worth it depends on your time horizon and stomach.

What About 5% or 20%?

The two portfolios shown here do not establish what 5% or 20% Bitcoin would have delivered. Those weights require separate backtests with the same dates and rebalancing rules.

Rather than listing all the numbers here, you can run your own backtest with any allocation, start date, and rebalancing frequency.

The Catch

Backtests are rearview mirrors. The decade from 2015-2025 included Bitcoin's transition from a niche experiment to a trillion-dollar asset class with spot ETFs and sovereign adoption. That history does not establish the scale or direction of future growth.

The question isn't whether a 10% allocation would have worked. It clearly did. The question is whether you believe Bitcoin's risk-adjusted return will continue to justify a portfolio allocation going forward. For a data-driven approach to sizing that allocation, see How Much Bitcoin Should Be in Your Portfolio? Our portfolio optimizer uses forward-looking asset assumptions and Portfolio Lab Bitcoin scenarios to explore the tradeoffs.