Why do stocks change after hours?

Related questions

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2. How soon can you buy a stock after selling it?
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4. What happens when future contracts expire?
5. Do futures trade on weekends?
6. What is lot size?
7. Can I buy stock after hours on Robinhood?
8. Can I sell a stock before it settles?
9. What is the best day of the month to invest?
10. What time of day is best to buy stocks?

Tags

1. #periods
2. #investor
3. #regular
4. #outside
5. #hours
6. #trading
7. #closes
8. #after
9. #standard
10. #through
11. #market
12. #securities
13. #stock
14. #exchanges
15. #period
16. #occurs
17. #investors
18. #exchange
19. #major