So, I have been trying to figure this out but I am not sure if I understood it thoroughly.
I do know that the price of a stock changes due to supply and demand. But sometimes the price plunges or soars when the market is closed (for example WFM losing 25% from when it closed on May 6th to when it opened on May 7th, or DMD on August 4th that went up 80% before the market even opened).
I know that there is pre-market and after hours market. So are the people trading during these time frames the cause of the change of the price? What or who makes the price of a stock change after 4.00 pm ET so abrutly?
Thank you (and sorry for some grammar mistakes but I am not from here)