How are weekly stock prices calculated??

Question

I noticed on Yahoo finance! that every Monday they say the weekly stock price (closing price) is that Monday's daily closing price. However, several days later, for the same date, the weekly stock price changes to a different number! What's the deal? How is the weekly stock price calculated?

Answer 1

Stock prices are calculated constantly while the exchange is open.  This occurs as people are buying / selling the stock constantly.  Yahoo is probably showing you an average or end of day price.  When you look at averages, they are calculated on rolling callender weeks / months / years etc...