What does it mean when people say "the market is up" or "down"?
They mean a major index, usually the S&P 500 or the Dow, closed higher or lower than the day before. It is an average of big companies, so your own stocks may have done something different.
When a news anchor says the market was up 1 percent, they are talking about an index, almost always the S&P 500 or the Dow Jones Industrial Average. An index is one number that summarises the prices of a set of big companies, so "the market is up" really means "the average of these large stocks is up."
That average hides a lot. On a day the S&P 500 rises 1 percent, maybe 350 of its companies rose and 150 fell. Your particular stock might have dropped 4 percent on its own news while "the market" had a great day. The index is a weather report, not a report on your garden.
It also weights big companies more heavily. A handful of giants like Apple, Microsoft and Nvidia make up a large share of the S&P 500, so a strong day for them can lift the index even when most stocks are flat. The Dow uses a stranger method that weights by share price, which is why it is quoted more from habit than usefulness.
For practical purposes: "the market is down" tells you the mood, and helps explain why your stock fell when nothing happened to it. It tells you very little about whether anything in your portfolio has actually changed.
Informational only, not financial advice. Updated September 4, 2026.
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