Volatility

Portfolio Volatility Explained

The statistical spread of your portfolio's daily returns

Formula

σ × √252

annualised standard deviation of daily portfolio returns, where 252 is the standard number of trading days per year.

What is the Portfolio Volatility?

Volatility — formally the annualised standard deviation of returns — measures how spread out your daily returns are around their average. A highly volatile portfolio has returns that swing dramatically day to day; a low-volatility portfolio moves in a tighter band. Volatility is not the same as risk, but it's a key component: high volatility amplifies both gains and losses and makes planning harder.

How to interpret it

Annualised volatility is expressed as a percentage. The FTSE All-World typically runs around 14–16% annualised volatility. Individual equities can be 25–50%. A well-diversified balanced portfolio should sit in the 8–15% range. Volatility above 20% suggests concentrated equity risk or exposure to highly speculative assets. Below 5% typically implies heavy bond/cash allocation.

What counts as a good Volatility?

< 5%Very low — cash-heavy or bond-heavy; limited growth potential

5% – 10%Conservative — typical of a balanced fund or defensive equity allocation

10% – 20%Moderate — standard for diversified equity portfolios

20% – 35%High — concentrated or growth-tilted; high upside and downside

> 35%Very high — speculative exposure; review diversification urgently

What affects your Volatility?

Asset class mix — equities are more volatile than bonds; alternatives vary widely
Sector concentration — tech, biotech, and energy tend to be high-volatility sectors
Geographic diversification — emerging markets add volatility; developed markets dampen it
Number of holdings — beyond 20–25 holdings, additional diversification reduces volatility slowly
Market regime — volatility is itself volatile; it clusters and spikes during crises

How Portivex uses Volatility

Portivex displays annualised volatility (σ × √252) computed from your daily return history. It appears in the MetricsGrid alongside Sharpe and Sortino so you can see the risk-return tradeoff at a glance. Volatility is also an input into the VaR calculation — rising volatility will increase your VaR figure in real time. The confidence tier flags when your volatility estimate is based on fewer than 60 trading days of data.

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Frequently asked questions

Is high volatility always bad?

No. Volatility is symmetric — it captures upside swings as well as downside ones. A growth investor with a long time horizon may be comfortable with 25% annualised volatility if it's associated with strong expected returns. The Sharpe and Sortino Ratios put volatility in the context of return, which is more useful for evaluating whether it's 'worth it'.

What's the difference between realised and implied volatility?

Portivex calculates realised (historical) volatility — the actual spread of past returns. Implied volatility is derived from options prices and represents the market's expectation of future volatility. Realised volatility is backward-looking; implied is forward-looking. Both are useful, but Portivex focuses on historical realised volatility as it's directly based on your actual holdings.

Does adding more holdings always reduce volatility?

Up to a point. Diversification reduces idiosyncratic (stock-specific) risk, but systematic (market) risk remains. Beyond roughly 20–30 holdings, additional diversification has diminishing returns on volatility — unless those holdings are truly uncorrelated. Adding more of the same sector or geography does little to reduce portfolio volatility.

Related metrics

See your Portfolio Volatility in real time.

Add your holdings and Portivex calculates your Volatility — with confidence context and plain-English interpretation tailored to your investor profile.

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