GlossaryGlossary

What Is Risk Contribution? Definition and Example

What risk contribution means, the formula, and a worked example showing how a 40% bond weight can carry less than a fifth of the risk.

Reviewed by:David, Senior AnalystPublished Oct 20, 2026Updated Oct 20, 20262 min readHow we research

Key takeaways

Risk contribution is the part of a portfolio’s total volatility that comes from one holding, combining its weight, its own volatility and its correlation with the rest.
Contributions add up to the portfolio’s volatility, so each can be read as a percentage share.
On Exent’s 5-year data, a 60/40 SPY/AGG portfolio got about 82% of its risk from stocks.

In this article

What is risk contribution?
The formula
Worked example
Why it matters for a self‑directed investor
Common mistakes

What is risk contribution?

It answers “which holding is driving my swings?” A small position in a very volatile stock can contribute more risk than a large position in a calm bond fund. Dollar weights hide this; risk contribution shows it.

The formula

Risk contribution of holding i = wᵢ × (Σw)ᵢ ÷ σₚ, where w is the weight vector, Σ the covariance matrix and σₚ the portfolio volatility.
The term (Σw)ᵢ ÷ σₚ is the marginal contribution to risk.
Percentage share = risk contribution ÷ σₚ. The shares sum to 100%.

Worked example

Holding	Weight	5-year volatility	Risk contribution	Share of risk
SPY (stocks)	60%	15.7%	9.3 points	82%
AGG (bonds)	40%	6.6%	2.0 points	18%
Portfolio	100%	11.3%	11.3 points	100%

Holding	SPY (stocks)	AGG (bonds)	Portfolio
Weight	60%	40%	100%
5-year volatility	15.7%	6.6%	11.3%
Risk contribution	9.3 points	2.0 points	11.3 points
Share of risk	82%	18%	100%

Computed from Exent’s data, as of Sep 30, 2026, with a 60-month correlation of 0.62 between SPY and AGG.

Why it matters for a self‑directed investor

It turns “I feel diversified” into a number. If three tech stocks supply most of your risk, the rest of the portfolio is not doing much diversifying. The risk contribution guide walks through a full portfolio, and a risk budget sets limits on it.

Common mistakes

Using volatility alone and ignoring correlation.
Mixing time windows for volatility and correlation.
Forgetting that a negative contribution is possible for a true hedge.

See what drives your portfolio’s risk with Exent

Upload a screenshot of your holdings, or a CSV, Excel, PDF or Google Sheet; no brokerage login.
Portfolio Analysis groups holdings that move together into correlation clusters, flags concentration and replays the portfolio through past crashes.

Check my portfolio

Exent is our product. Educational content, not investment advice.

Frequently asked questions

Yes. If a holding is negatively correlated with the rest of the portfolio strongly enough, adding it lowers total volatility, and its contribution is negative.

No. Weight is the share of dollars. Risk contribution is the share of volatility, which also depends on each holding’s volatility and correlation.

You need weights, each holding’s volatility and the correlations between holdings, all measured over the same period.

: .-++++=: .-=+**+-. .:=+*#*=:..::-+##*+-:. .-+**+++=:. .:::-=+**********++===++***+++*###*+=--:. .:==+*#*+-:..::-+##*+-:. :=**++=: .-=+**+-. .:=+*#*-...: . -++*+=: .:=+**+-. .:-+*#*=:..::=+##*=-:...:=***++=:. .:-=+*###*++==--:::::::...:---==+*##**++=-. .:-=+###*=-:...-+**++=: :=++*+-. :-=***=:..:-=*##+-..: :=+*++-. :=++*+=. :-=*#*+-..::=+##*=-:...-+*#*+=-. :-=+*###*+=--:. .... .::..:-=+++****=-:..::-=*#*+=-: .-=++++=. .-=+**+-...:=+##*=:.::-+##*=::. .-++++=: .-=+**=: .-=+*#+-...:-+##*=-::.:-+##*+=:. .-=++***+=-:::.. ..:-----:::::::. .:-=+*###*=-:.. :=+**++-. .-=+**+-. .:-+*##+:..:-=*##+-:..:=*#*+-:. :=+*++-. :=+**+-. .:=+*#*-...:-+*##+-:.::-+##*=-:. :=++**++-:...::::-==+++++****++===-:....:::-+*#*+==:. .-=+**+-. .:-=*##+-:.::-+##*=::.:-+##*=-:..-+#*+=:. .-++++=: .-++**=: :-=***=:..:-=*##+-:.::-+##*=-:...:=***++-: .:-==*###**+**####*******+=-::...:-+**++=-. :-=+##*-:..:-+###+-:..:=*#*+-:..:=*#*=-: :=**+=-. :=++++-. :=+**+-. .-=+**+-...-=+##*-:.::-+##*=-:...-+***+=-. .:-=+*####*+==========++*###*+=-:. .-=+***+-...:-=*##+-::.:-*##+=-:..-+#*+=-. .-+**+=: .-++++=: :=+*+=: .-=+**=: :-+***=: .:-+*#*=:..:-+###+-::.:-+##*=-:. .-=++****+---::. .::::--+****++=-. .:-+*##+-::.:-+##*=-:..:=*#*+-: .=**++-. :=+*++-. :=+**+: -++*+=. :=+**+-. .-=+**+-..:-=*##+-..:-=*##+-::.:-+##*=-:. :=+++*++-:...:.. ...:.. .:-=+**#*=:..::-+##*+-:...-+#*+=-. -+**+=: .-++*+=: .-++*+=. :=+**+- =+**+- .-=+**=: :-=*#*=:..:-+*#*=:.::-+##*=::.:-+##*=-:. .-+**++=-: .::---====---:. .::-=*##*=-:...-+##+=-: :=+*++-. .=++++-. :=+**+-. .-=+**+: .:-=*#*= =+**=: :-=***=. .:=+*#+-..:-=*##+-..:-=*##+-:.::=*##+-:...-+**++=:. .:-==+*###*+++++=-:..:::=*##*=-:. .-+**+=: -=+*+=: .-=+**=: :-=*#*=. .:=+*#+-..:-=*##+ =+**=. .:=+**+-. .-=*##+:..:-+*#*=:.::-+##*-::::=*##+=::..-+##*=-: :-=++*###**+++*###*=-::. .-+**+=-. :=++*+=. :-+**+-. .:=+*#+-..:-=*##+:..:-+##*=:.::=*##+ +**+-. .-=+**+:..:-+*#*=:..:=+##+-:.:-=*##+-:.:-+##*=-:..:+*#*=-:. .:=++***+=------=+*##*+=-. .-++*+=: .-=+**+: .-=*#*=:..:-+*#*=:.::=*##+-:.:-+##*=::.:-*##+ +**+-. :-=*#*=:..:-+##*-..:-=*##+-:.:-+##*=::.:-*##+-:..:=*#*+-:. .-+**++=-:. ..:...:-=+*++=-. :-+***=. .:-+*#*-...:=+##+-..:-=*#*=::::-+##+-::.:=*#*=-:..-+##+ +*#+:..:-+*#*=:..:=*##+-:.:-+##*=::::-*##+-:..:=*#*=-:..:+##+=-. .:+**++-: .::::. :-++**+:. .-=+##+:..:-=*#*=:..:-+##*-::::=*##+-:.:-+##*=::.:=*#*+-:..:+##+ *##+:..:-+##*-:.::=*##+-:::-+##*=::.:=*##+-:..-+##*=-...-*#*+-:. .=***+-: :-====-: .:-+*#*=:..:-+##*-:.::=*##+-:.:-+##*=::.:=*##+-:..:+##+=-...-*#*+-:. :+**+ *##=:..:-+##*-:.::=*##=-:.:-+##+-:..:=*#*=-:..-+##+=:. :=*#*=-: :+**+=:. .-=++**#*+-..:-=*##+-:.:-+##*=::.:=*##+-:..:+##*=-:..-*#*+-:..:+**+=-. .-***+-: :=**+ *##=::::-+##+-::::=##*=-:.:-*##+-:..:=##*=-:..-+#*+-:. :=**+=-. .-+**+=: :=+*+++##*=::::=*##+-:.::+##*=-:.:-*##+-:..:+##*=-...-*#*+-: :=**+=-. .-+*++-. :=+*+ ##*=::.:-*##+-:..:=##*=-:..-*#*+-:..:=*#+=-. .-+**+-: :=**+=-. .-+*++=. :=++++*##*=::.:=*##+-:..:+##*=-:..-*#*+-:..:+**+=-. .-***+-: :=**+=: .-+*++-. :=+++ ##*=-:..-*##+-:..:=*#*=-...-+#*+-:. :=**+=-. .-+**+=: .=+*+=-. -=+*+=: .-=+*###*=-:..:=*#*=-:..-+##+=:...=*#*=-: :+**+=:. .-+*++-. :=**+=: .-++++-. :=+** ##*=-:..-+#*+-:. :=**+=-. .-+**+=: .=**+=-. :++++=: .-++*+-. :=+**+-. .:--=++=-:::.:-*##+=:...-*#*+-:. :=**+=-. -+**+=: .=+*+=-. :=+++=: .-++*+-. .-=+** *#*=-: .-+**+=:. .=**+=-. :+**+=: .-++++-. :=+**+: .-=+**=: :-=+##+-:...........::-+##*=-:..:=*#*=-. :+**+=:. .-+*++-. :=+*+=- .-++*+=. :=+**+- .-=+** ***=-. :+**+=: .-+*++-. :=+++=: .-=+*+=. :-+**+-. .:=+*#*-:..:-+*##*=--:. .:--=*##*=-:...-*#*+=:. .-+**+-: .=+*+=-. :=+*+=: .-++*+-. :=+**+: :-=*** +*++-. :=+*+=: .-++*+=. :=+**+-. .:=+**+: :-=*#*+:..:-=*##+-::.:-=*##*+==------==+*##*=-:...-+##+=-. :+**+=-. :++*+=: .-++*+=. :=+**+-. .-=+**=: .:-+*#* ++++=: :=++*+-. .:=+**=: .-=***=. .:-+*#*-...:=+##*=::::-+##*+-:.. .-++++**##***++**#*+-::..:-+##*=-:. .=***+=: .-+*++-. :=++*+-. .-=+**+: :-=*#*=. .:=+##+ =+*+=: .-++**=. .:=+**+-. .-=+##+-..:-=*##+-:.:-=*##+-:...-+##*+=:. .:-==+*###**++++=-:..:::=*##*=-:. .-+**+=:. :=+*+=: .-=+**=: .-=***=. .:=+*#+-..:-=*##+ =+**+-. .-=+**=:..:-+*#*=:..:-+##*=:.::-+##*=::..-+##*=-:. .-++*+++-: .::::--====--:. .::-+*##*=-:. .-+**+=-. :=+*++-. :=++*+-. .:=+**+-. .-=+##+:..:-+*#*= -+*#*=...:=+##+-..:-=*##+-:.:-=###+-:..:=*#*+-:. .-+**+=-. .:=++*#*+-:::.. .::.. .:--=+###*=-:...-+**+=-: .-+*++=: .-=+**=: .-=+**=: .:-+*#*=:..:=+##*- -=*##=:..:-+##*=::::-+##*=::..-*##+=-. .-+**+=-. .-++**+-. .:-=*###*+=--:.....:::..:--=++*##*+-::..:-+##*=-: .-+**+=-. :=+**+-. .:=+*#+-...-=+##+-..:-=*##+- :=*##+-::::=*##+-:..:=*#*=-:. :=***+-: .-++++=-. :-=+*#*=:..:::-=****++*+++======++********=-:..::-=*##*=-:. .-+**++-. .-++**=: :-=***=:..:-=*#*=:..:-+##*=: :-+##*=-:..-+##+=-. .-+**+=:. :++*++-. :-++**+-. .:-=*##*+--:. .:==++*####**++*####**++==:. .:--+###*=-:. .-+**++-: .-=+**+: .-=+*#+-...-=+##+-..:-=*##+-: .:=*#*=-:. :=**+=-: :=+*++-. .-=+**+:. .:-+*##+-:::::=+##*+=-:. .:--==+**++++****+==--: :--=*###+=-:...-+**++-: .-=+**+-. :-+***=:..:-+*#*=:..:-+##*=:: .-+**+=:. .-+**+=: .-=+**+-. .:-+*#*+:..::-+###+=-:. .:=+***++=-:........::-----::::::.. :-==+*##*=-::..:=*#*+=-: .:=++++-. :-=+**+:..:-=*##+-..:-=*##+-:: :=+*++-. :=++*+=. :-=***+-..::=+##*=-::.:-+*#*+=-: :-=+*###*+=--:. ..:. .:::::-=+++****=-:..::-=*##+=-:. .-=+*++=: .-=+**+-. .:=+##*=:.::-+##*=::. .-=+**=: .-=+**+-...:-+##*=-::::=*##*=-:. .:=+*+++=:. .::-=+*##**++==--::::::...::---=+**#**+++=:. ..:-=+###+=-:. .-+**++=: .-=+**+-. .:-+*#*=:..:-=*##+-::: . :-+***=:..:-=*##+-:.::=*##*=-:..:-+**+=-: :-=+*#*+=:::...:-=++++*###**++=+++++++++**###*+==-:. .:-=+*##*+-::...-+**++-: .:=+**+=. :-=*##+-..::=*##*-::.:

See what your portfolio is really made of.

Upload a screenshot of your holdings and get concentration, overlap, crash exposure and a risk-matched benchmark in about a minute.

Check my portfolioLimited offer$1.95 for unlimited checks· unlimited checks

Educational content, not investment advice. Examples are illustrative; past performance does not guarantee future results.

DISCLAIMER: Exent AI is an informational research platform and does not provide investment advice, financial advice, or act as an investment adviser, broker-dealer, or fiduciary. All content, analytics, and model outputs are provided for educational and informational purposes only and should not be relied upon as a recommendation to buy, sell, or hold any financial instrument. Investing involves risk, including the possible loss of principal. Exent AI does not execute trades, hold customer funds, or provide brokerage services. Past performance and hypothetical results are not indicative of future results. Third-party data and AI-generated outputs may be incomplete or inaccurate.