DEFINITION of 'ExPost Risk'
A type of risk measurement technique that uses historic returns to predict the riskiness of a certain investment in the future. This type of risk measure is the equivalent of the statistical variance of an asset's returns relative to its mean.
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BREAKING DOWN 'ExPost Risk'
Using historic returns as a measure of future risk has been a traditional method used by investors to determine the riskiness of a given asset. Expost risk is often used in value at risk analysis  a tool used to give investors a best estimate of the maximum amount of loss that they could expect to incur on any given trading day.
RELATED TERMS

ExPost
Another term for actual returns. Expost translated from Latin ... 
Variance
The spread between numbers in a data set, measuring Variance ... 
Historical Returns
The past performance of a security or index. Analysts review ... 
MeanVariance Analysis
The process of weighing risk against expected return. Mean variance ... 
Return
The gain or loss of a security in a particular period. The return ... 
Variability
The extent to which data points in a statistical distribution ...
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RELATED FAQS

Is tracking error a significant measure for determining expost risk?
Before we answer your question, let's first define tracking error and expost risk. Tracking error refers to the amount by ... Read Answer >> 
How reliable is the mean variance analysis of an investment?
Learn how mean variance analysis is used to determine the historical volatility of an asset and how future volatility may ... Read Answer >> 
Is variance good or bad for stock investors?
Learn how high variance stocks are good for some investors and how diversified portfolios can reduce variance without compromising ... Read Answer >> 
What is the difference between expected return and variance?
Learn about expected return and variance, the difference between the two measures and how to calculate the expected return ... Read Answer >> 
Can a mean variance analysis be done for any investment?
Learn how mean variance analysis is used in modern portfolio theory to create an optimal mix of assets to maximize return ... Read Answer >> 
What types of assets lower portfolio variance?
Learn what type of assets reduce portfolio variance and how modern portfolio theory uses correlation coefficients. Read Answer >>