When the market drops, don't drop out.
The story so far You've got VOO in your Oakline account and $10 going in every Friday. Then one morning the app is red. Your fund is down 4% this week, the news says "markets tumble," and a friend texts that he sold everything. You wonder if you should too. This lesson is about that moment, because it will come, more than once.
A bear market is a drop of 20% or more from the market's last high. Smaller dips happen almost every year.
Drops are the price of stocks' higher long-run returns. Selling in a panic turns a temporary drop into a permanent loss.
Invest only money you won't need for years, keep an emergency fund, keep buying on a schedule, and don't sell because prices fell.
Financial advisors spend much of their job talking clients out of panic selling. Portfolio managers at funds decide how much risk to hold.
What you're looking at: a sketch shaped like the real 2020 drop, when the S&P 500 fell 34% in about a month and was back at a new high five months later. The person is holding on instead of jumping off.
Drops are normal. Selling is optional.
Every chart below uses real S&P 500 history. Look at how often prices fall, how deep the worst falls went, and what time does to the odds.
Prices swing every year
How much and how fast prices move up and down is called volatility. Stocks are volatile: some years are great, some are awful, and you can't tell which is coming. Drag across the chart to see each year.
- Volatility
- From 1928 to 2025, the S&P 500 with dividends fell in 26 of 98 years, about 1 in 4. Its worst year was 1931, −43.8%. Its best was 1954, +52.6%.
What you're looking at: real data. Each bar is one year from 1928 to 2025, showing the S&P 500's total return including dividends, from Aswath Damodaran's NYU dataset. Bars above the middle line are gains, bars below are losses. The scale runs from −50% to +55%.
Corrections and bear markets
A correction is a drop of 10% or more from a recent high. A bear market is 20% or more. The opposite, a long climb, is a bull market. Getting back to the old high is the recovery. Tap a bear market to read what happened.
- Correction
- From February to April 2025, the S&P 500 fell about 19% as new tariffs shook markets. It was back at a new high by late June.
- Bear market
- From January 3 to October 12, 2022, it fell 25.4% as interest rates jumped.
- Recovery
- It passed its January 2022 high on January 19, 2024, about 2 years after the drop began.
What you're looking at: real data for six S&P 500 bear markets since 1970. The orange bar is how far prices fell from the high to the bottom. The gray bar is how many months passed from the old high until prices were back to it. These use prices only; counting dividends, recoveries came a little sooner.
Time shrinks the chance of a loss
Your time horizon is how long until you need the money. Over one year, stocks lose money often. Over long stretches, losses got rare, because good years had time to outweigh bad ones. Slide to pick how many years you hold.
- Time horizon
- Money for a car next year has a 1-year horizon: about 1 in 4 one-year stretches lost money. Retirement money at 20 has a 45-year horizon. Every 20-year stretch since 1928, all 79 of them, ended with a gain.
What you're looking at: real data. Each small square is one stretch of the length you picked, starting in a different year from 1928 on, using the S&P 500's yearly total returns. Orange squares lost money from start to end; green squares gained. Past results don't promise future ones.
Why selling after a drop hurts
Panic selling means selling because prices fell and you're scared. It locks in the loss, and then you have to guess when to get back in. Some of the market's best days come right after its worst ones: J.P. Morgan found that over the 20 years it studied, 7 of the 10 best days came within two weeks of the 10 worst, and missing just those 10 best days cut an investor's ending value roughly in half. Part of the urge comes from loss aversion: psychologists Daniel Kahneman and Amos Tversky found that losses feel about twice as strong as gains of the same size.
- Panic selling
- $10,000 in the S&P 500 at the start of 2008 was worth $6,345 after the year's −36.6%. Sell then and hold cash, and five years later you'd have about $6,380. Stay invested, and by the end of 2013 it was about $14,350.
- Loss aversion
- Watching $100 disappear feels about as bad as gaining $200 feels good. That's why a red week feels like an emergency even when it isn't.
Keep buying on a schedule
Dollar-cost averaging means investing the same amount on a schedule, like $100 a month, no matter what. When prices drop, the same $100 buys more shares, so drops quietly help you. Drag the middle month's price.
- Dollar-cost averaging
- $100 a month at $50, then $25, then $50 buys 2 + 4 + 2 = 8 shares for $300. At $50 they're worth $400, even though the price ended where it started.
What you're looking at: a calculator with made-up prices, not market data. Each month you invest $100. The coins show how many shares $100 buys at that month's price. Month 1 and month 3 stay at $50.
The real protection: a plan made before the drop
Drops hurt most when you need the money during one. So keep money you'll need within about five years, like your emergency fund or a car down payment, in savings, not stocks. With that cushion, you never have to sell low to pay a bill.
- The plan
- Your $3,600 emergency fund sits in savings. Your VOO is for 10+ years from now. When the market drops 25%, nothing in your life forces a sale, so you keep your $10 a week going in.
Two minutes. Just listen.
Tap any line to jump to it.
Hold or fold: ride real history.
Three rounds, each a real stretch of S&P 500 history, one year at a time. You start each round with $10,000 in an index fund and add $100 a month. After each year's news, decide: stay invested, or sell and sit in cash, which earns that year's real Treasury bill rate. You won't know which years they are until the round ends.
What you're looking at: real yearly S&P 500 total returns and real 3-month Treasury bill returns from Damodaran's NYU dataset. The headlines describe what really happened those years. Your $1,200 a year goes in at the start of each year after the first, into wherever your money is. Taxes and fees are left out.
The logic, step by step.
Four calculations explain why drops feel so big and why time and steady buying help.
Step 1: The size of a drop
Subtract the old value from the new value, then divide by the old value.
- 2008
- $6,345 − $10,000$10,000 = −$3,655$10,000 = −36.55%.
Step 2: The gain you need to get back
After a drop, you're starting from a smaller amount, so climbing back takes a bigger percent than the fall. Divide the drop by what's left.
- Down 50%
- 0.501 − 0.50 = 0.500.50 = 100%. $10,000 falls to $5,000, and $5,000 must double to get back.
- Down 36.55%
- 0.36550.6345 ≈ 57.6%. After 2008, the S&P 500 gained 25.9% in 2009 and 14.8% in 2010, and with dividends it was back above even by the end of 2012.
Step 3: Your average cost when you buy on a schedule
Divide all the money you put in by all the shares you got.
- $50, $25, $50
- $3008 shares = $37.50 a share, below the $41.67 average of the three prices, because $100 bought extra shares in the cheap month.
Step 4: The chance of a loss over a stretch
Count the stretches that lost money and divide by all the stretches of that length.
- 5 years
- 1194 ≈ 11.7%.
- 10 years
- 589 ≈ 5.6%.
- 20 years
- 079 = 0%.
Worked example: a bear market with your $10 a week
- Before. You hold $2,000 of VOO for retirement and $3,600 of emergency savings. You add $10 every Friday.
- The drop. Prices fall 25%: $1,500 − $2,000$2,000 = −25%. Your account shows $1,500.
- The urge. Loss aversion says sell. Your plan says nothing changed: you won't touch this money for decades, and bills come from savings.
- Keep buying. Each $10 now buys shares about 25% cheaper than before the drop.
- The recovery. To get back, prices need 0.250.75 ≈ 33.3%. In 2022's bear market, that took until January 2024, and your cheap Friday shares gained even more.
Bears sleep through the winter.
A black bear doesn't hunt through a blizzard. It eats well in the fall, builds up fat, and then spends the winter in its den, living off that stored fat for months. When spring comes, it walks out into a world with food again.
What you're looking at: an illustration, not data. A bear sleeps in a snowy den while snow falls outside.
Why this sticks. In a bear market, act like a bear in winter. Your emergency fund is the fat you stored up, so you don't have to go out and sell in the storm. Wait in the den, keep your small weekly buys going, and walk out when spring comes.
The page you'd copy down.
- Volatility: how much prices swing. The S&P 500 fell in 26 of 98 years from 1928 to 2025, about 1 in 4.
- Correction: down 10% or more. Bear market: down 20% or more. Recovery: back to the old high, from 6 months (2020) to over 7 years (2000 and 1973).
- Gain needed to recover = drop1 − drop. Down 50% needs +100%.
- Time horizon: when you need the money. Losing stretches since 1928: 1 year 26.5%, 5 years 11.7%, 10 years 5.6%, 20 years 0%.
- Panic selling locks in losses and risks missing the best days. Loss aversion: losses feel about twice as strong as gains.
- Dollar-cost averaging: the same amount on a schedule buys more shares when prices are low.
- Money needed within about five years belongs in savings, not stocks.
Fill in the blanks
Grab a friend or a study group.
Ask someone who lived it
Interview a parent or older friend about 2008 or 2020. What did they do with their investments? What do they wish they'd done?
Recovery math race
Call out a drop, like 20%, 40% or 60%. First to say the gain needed to get back, 25%, 67% or 150%, wins the round.
Write the rule together
As a group, write one sentence each of you would read before selling in a drop. Compare and pick the one that would actually stop you.
Just you and your money.
These stay on this device. Nobody else sees them.
Exam-style questions.
Written the way a college exam would ask them. Each right answer on the first try is worth 10 xp.
On the job: you're the financial advisor
A 30-year-old client calls. Her retirement account, all in an S&P 500 index fund, fell from $40,000 to $30,000 in a bear market. She wants to sell everything "until things calm down" and buy back later. She has a $9,000 emergency fund and adds $500 a month to the account.
Your task: work out the size of her drop and the gain needed to get back, then explain what selling now would require to work out, and what you'd suggest instead.
See a model answer
The numbers: $30,000 − $40,000$40,000 = −25%. To get back she needs 0.250.75 ≈ 33.3%, so $30,000 must grow by $10,000.
What selling requires: she'd have to be right twice, selling before more drops and buying back before the rebound. Big rebound days often come within days of the worst days, and in 2022's bear market, prices were back at the old high by January 2024. If she waits for things to feel calm, she'll likely buy back higher than she sold.
What to suggest: her money is for retirement, 35 years away, and she has $9,000 of emergency savings, so nothing forces her to sell. Keep the $500 a month going: each deposit now buys about a third more shares than before the drop. If the swings are truly unbearable, the long-term fix is a mix with some bonds chosen calmly, not a sale in a panic.
From one scary drop to a lifetime of them.
What you're looking at: a map of where this lesson fits in the course. Read it left to right: the lessons that come before, this lesson in the middle, and the later lessons that build on it.
- Before · Unit 5Buy your first $10
- Before · Unit 5Why invest at all?
- You are hereMarket drops
- Next · Unit 5401(k) and Roth IRA
- Later · Unit 10Why we make bad money choices
- Later · Unit 9Booms and recessions