# Understanding the VaR example on wikipedia

The example says:

For example, if a portfolio of stocks has a one-day 5% VaR of $1 million, there is a 0.05 probability that the portfolio will fall in value by more than$1 million over a one day period if there is no trading.


What is the reason for the clause 'if there is no trading'?

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If there is trading the portfolio caracteristics (assets risk return weights) might change therefore the VaR will change – adelm Jan 28 '14 at 16:44