I can't seem to find an answer to my exact question.
I want find how much on average a stock or the stock market goes up during an up week (or month) and down during a down week (or month). Let's say it goes up 5% the first week up 10% the second week down 20% the third down 10% up 15% up 20% down 5%.
Can I simply average the percentages? In this case the average for up weeks is (5+10+15+20)/4 = 12.5% and down weeks is (20+10+5)/3 = 11.67%. Or would I need to do something else?
I found a similar question here
but no one really addressed it.