Why the stock market goes up and down and what you can do about it

Centuries-old wisdom tells us to buy low and sell high—whatever it is we’re buying. But when it comes to the stock market, it’s not so easy to do. Stock market values go up and down from day to day, even minute to minute, making it difficult to know exactly what to do and when. We’ll break down some of the mechanics that cause all the changes and help you understand what it could mean for your own investment strategy.

Woman with hands on head facing a blue screen with dates, graphs, and data.
This chart shows that the value of the stock market has gone up from 2012 to 2023
This chart looks at a shorter period of time to show how much the market changes from day to day (2021 to 2021)
With Emily Roland, Co-Chief Investment Officer, John Hancock Investment Management
Month Price of the investment Month Price of the investment
January  $10 July $12
February $8 August $9
March $4 September $5
April  $7 October $6
May $11 November $10
June $12 December $11