Investing EssentialsLesson 2

How Stock Prices Work

Why do prices go up and down? It's simpler than you think - and once you understand it, the market makes a lot more sense.

8 min read
Beginner
Updated: December 2025

Educational purposes only. This content does not constitute investment advice. Read our disclaimer

StockCram is not a broker-dealer, investment adviser, or financial institution. All content is for educational and informational purposes only and should not be construed as personalized investment advice. Consult a qualified financial professional before making investment decisions. Past performance does not guarantee future results.

TL;DR

Stock prices change because of supply and demand. If more people want to buy than sell, the price goes up. If more people want to sell than buy, the price goes down. That's it. Everything else is just explaining WHY people buy or sell.

Supply and Demand: The Only Thing That Matters

Every financial news headline, every analyst report, every earnings call - they're all just different ways of saying: "Here's why people might want to buy or sell."

In the short run, the market is a voting machine. In the long run, it's a weighing machine.

Howard MarksCo-founder, Oaktree Capital

Price Goes UP

More buyers than sellers. Buyers compete by offering higher prices to get shares. Sellers say "I'll wait for a better offer" and prices climb.

Price Goes DOWN

More sellers than buyers. Sellers compete by accepting lower prices to unload shares. Buyers say "I'll wait for a discount" and prices fall.

Supply & Demand in Action

The three scenarios that determine price direction

ScenarioEffectReason
More buyers than sellersPrice goes UPBuyers compete, bid higher
More sellers than buyersPrice goes DOWNSellers compete, accept less
Buyers and sellers balancedPrice stays STABLENo one needs to budge

What Actually Moves Stock Prices?

Now the real question: what makes people want to buy or sell? Here are the biggest factors:

1. Earnings (The Biggest One)

Every quarter, companies report how much money they made. Beat expectations? Stock jumps. Miss expectations? Stock drops. It's not about being "good" - it's about being better or worse than what everyone expected.

2. News & Events

CEO steps down. Drug gets FDA approval. Factory catches fire. Competitor launches better product. Any news that affects future profits moves the stock.

3. Market Sentiment (Fear & Greed)

Sometimes the whole market moves on emotion. Panic selling in a crash. FOMO buying in a bubble. Rational? Not always. But it moves prices.

4. Interest Rates & The Economy

When rates go up, borrowing costs more, companies earn less, and stocks often fall. When rates go down, money is cheap, companies grow, and stocks often rise.

What Moves Stock Prices

Key factors and their typical impact

FactorImpactExample
Earnings ReportsHighBeat expectations → up 5-20%
News & EventsHighFDA approval, CEO scandal
Economic DataMediumJobs report, inflation numbers
Analyst RatingsMediumUpgrade from "hold" to "buy"
Overall Market MoodHighFear/greed affects everything

A Year in the Life of a Stock

Here's what a typical stock might look like over one year. Notice how it bounces around but trends upward over time. This volatility is normal - don't panic at every dip.

Example Stock Price Over One Year

Normal volatility: Up 42% for the year, but dropped 15% in June alone

Example Stock Price Over One YearNormal volatility: Up 42% for the year, but dropped 15% in June alone1521391251129885100Jan105Feb98Mar112Apr108May95Jun103Jul118Aug125Sep122Oct135Nov142DecStock Price ($)
Example Stock Price Over One Year

Key Insight

This stock ended up 42% for the year - a fantastic return! But at one point (June), it was down 15% from its April high. If you panicked and sold in June, you would have missed the recovery. Short-term drops are normal.

The "Priced In" Concept

This confuses a lot of beginners. You'll hear people say "It's already priced in."

Here's what it means: stock prices reflect everyone's best guess about the future. If everyone already expects Apple to have a great quarter, that expectation is already built into the price. When the good news actually arrives, there's no surprise - so the price doesn't move.

Real Example

Scenario: Tesla is expected to sell 500,000 cars next quarter.

If they sell 550,000: Stock jumps - they beat expectations!

If they sell 500,000: Stock barely moves - exactly what everyone expected.

If they sell 450,000: Stock drops - they missed expectations.

Why This Matters For You

Understanding price movements helps you stay calm when your stocks drop. Here's the practical takeaway:

Daily moves are mostly noise. Unless something fundamental changed about the company, a -3% day means nothing.

Long-term matters more. Over years, prices follow earnings. If a company keeps making more money, the stock will eventually reflect that.

You can't time the market. Professional traders with supercomputers can't consistently predict short-term moves. You definitely can't. Focus on the long game.

Key Takeaways

  • It's all supply and demand - More buyers = higher prices. More sellers = lower prices. Everything else explains WHY people buy or sell.
  • Expectations matter more than reality - Stock prices react to surprises, not just good or bad news. "Priced in" is real.
  • Short-term moves are mostly noise - Don't panic at daily swings. Focus on years, not days.
  • Long-term, prices follow earnings - If a company keeps making more money, the stock will eventually reflect that. Be patient.

Continue Learning

Frequently Asked Questions

Because expectations were even higher. If analysts expected $2.00 earnings and a company reports $1.90 (still great!), the stock often drops. The market had already 'priced in' higher numbers. It's not about being good - it's about beating what everyone expected.

Not in the short term. Prices are driven by emotions, news, and momentum. In the short term, stocks can be wildly overvalued or undervalued. But over the long term (5-10+ years), prices tend to follow actual business performance.

Depends on the stock size. For tiny 'penny stocks,' yes - a single big order can move the price. For large companies like Apple or Amazon, it takes massive institutional buying/selling to move prices. That's why market cap matters.

When fear or optimism hits the whole market, investors sell or buy everything. During panics, even great companies fall. During manias, even terrible companies rise. This is 'correlation' - and it's why diversification doesn't always protect you in crashes.

Milliseconds. Modern markets are electronic, and prices update constantly during trading hours. On average, the S&P 500 changes direction every few seconds. That's why checking prices obsessively is pointless - you're seeing noise, not signal.

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