Risk Contribution
The share of total portfolio volatility that a single position contributes.
Risk contribution breaks a portfolio's total volatility down across individual positions, it shows where the swings really come from, not just how much each is worth. It combines three things: a position's weight (its value share), its own volatility, and its correlation with the rest of the portfolio. That is why a position small in amount but very volatile and strongly correlated with the whole can account for a disproportionately large share of risk. All contributions sum to 100%. The key insight: value share ≠ risk share. A coin that is 10% of the portfolio may contribute 30% of its swings, it "rules" the volatility. It is a measure of risk structure, descriptive and historical, not a recommendation to change or a signal.
In plain words
Tells you which position truly drives the swings of the whole portfolio. Sometimes a coin small in amount but very jumpy accounts for most of the stress.
Example
A small, very volatile altcoin is only 8% of the portfolio's value but a full 35% of its risk contribution, it, not the large BTC position, swings the whole the most.
Also known as: risk contribution, wkład do ryzyka, wkład w ryzyko, внесок у ризик