value at risk Q

There is a problem in the CFAI text that has us calculate value at risk, which I know the formula inside & out. BUT, I feel like I have come across problems like this one where if they want WEEKLY value at risk, so you need to divide the expected return by 52 weeks, and do the same with the standard deviation…but I think I’ve come across other problems where there was NO adjustment needed to both those items…is that because those problems must have been daily value at risk? OR, if they want daily value at risk, would I divide standard deviation by route 365?

Or in otherwords, when is that adjustment (from annual return & deviation) necessarily? Always?

Thnx!

Read the problem careful to figure out the data they provide. Sometimes its already in the right measurement period.