The VaR of a portfolio at the 99% confidence level is $250,000 when mean return is assumed to be zero. If the assumption of zero returns is changed to an assumption of returns of $10,000, what is the revised VaR?

The VaR of a portfolio at the 99% confidence level is $250,000 when mean return is assumed to be zero. If the assumption of zero returns is changed to an assumption of returns of $10,000, what is the revised VaR?
A . 260000
B . 240000
C . 273260
D . 226740

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Answer: B

Explanation:

The exact formula for VaR is = -(Z + ), where Z is the z-multiple for the desired confidence level, and is the mean return. Now Z is always a negative number, or at least will certainly be provided the desired confidence level is greater than 50%, and is often assumed to be zero because generally for the short time periods for which market risk VaR is calculated, its value is very close to zero.

Therefore in practice the formula for VaR just becomes -Z, andsince Z is always negative, we normally just multiply the Z factor without the negative sign with the standard deviation to get the VaR.

For this question, there are two ways to get the answer. If we use the formula, we know that -Z= 250,000 (as =0), and therefore -Z – = 250,000 – 10,000 = $240,000.

The other, easier way to think about this is that if the mean changes, then the distribution’s shape stays exactly the same, and the entire distribution shifts to the right by $10,000 as the mean moves upby $10,000. Therefore the VaR cutoff, which was previously at – 250,000 on the graph also moves up by 10k to -240,000, and therefore $240,000 is the correct answer.

The other choices are intended to confuse by multiplying the z-factor for the 99% confidence level with 10,000 etc.