"The central bank raised its policy rate." When that one line flashes on the news, the stock market wobbles by lunch and the real-estate forums are still arguing at 2 a.m. Rates are just a number. So why do perfectly calm stocks, home prices, and bonds all twitch at the same moment? Think of rates as a hidden "common exchange rate" sitting behind every asset price. Move it, and almost everything moves with it. Let's cut that connection into three effects.

The gist, up front. When rates rise, three things happen at once. The present value of money you'll get later shrinks; parking cash somewhere safe suddenly looks appealing; and borrowing to buy something turns into a heavier load. All three push the same way, pressing down on risky-asset prices. One at a time.

Effect 1 — The Discount Rate: Future Money Gets Shaved Down

Which is worth more: "a million won a year from now," or "a million won in your hand today"? The one in your hand, obviously. Get it today and you can put it to work for a year and earn interest. So when we translate future money into present value, we shave it down by some percentage. That percentage is the discount rate. Fancy name, but that's the whole idea.

Say the discount rate is 5% per year. Then 1,050,000 won a year from now counts as equal to 1,000,000 won today. Now bump the discount rate to 10%. That same 1,050,000 won a year out is worth only about 955,000 won in today's terms. The future amount didn't change — only the shave got bigger — so its present value shrank.

Here's the key. The discount rate moves with interest rates. When market rates rise, the discount rate rises too, and the present value of future cash flows shrinks across the board. Stocks are the textbook case. A stock's price is really "the present value of all the profits the company will earn in the future, added up." When the discount rate goes up, that sum gets smaller, so in theory the fair price falls.

And here's where people get a jolt. Assets that lean on profits far in the future get hit hardest. That's exactly why a growth stock — "losing money now, but expected to earn big in ten years" — swings far more violently on a rate hike than a company already booking steady profits today. The further out the money sits, the more years it gets discounted, so even a small rise in the discount rate carves a big chunk off its present value.

Effect 2 — Opportunity Cost: When the Safe Choice Suddenly Looks Pretty

When you decide where to put your money, you're always comparing alternatives. You could take on risk with stocks or real estate — or you could just tuck the cash into a bank deposit or a government bond and sleep fine. That comparison is the opportunity-cost effect.

When rates are low, a deposit pays a sliver of interest. So you think, "If that's all I get, I might as well take some risk for a better return," and you drift toward stocks and property. But when rates climb high enough, the whole thing flips.

Say a safe deposit or government bond pays 5% a year. If you can collect 5% without a single sleepless night, then for a price-swinging risky asset you'll demand "a return far higher than that." The price of taking on risk goes up. And when the return people demand from a risky asset rises, the fair price they'll pay for that same asset falls.

You can feel this in everyday life.

• Low rates: "Deposits are hopeless" → money floods into risky assets → upward price pressure
• High rates: "Why bother taking the risk?" → money drains into safe assets → downward pressure on risky-asset prices
• The higher the interest on the safe choice, the more a risky asset must "prove" a higher expected return to get chosen

So interest rates set the height of the bar a risky asset has to clear. Raise the bar, and it gets a lot harder for an ordinary asset to climb over it.

Effect 3 — Financing Cost: When Borrowing to Buy Gets Heavy

If the first two were about "calculation" and "comparison," this one is the grittier matter of "cash flow." A great many assets in this world are bought with borrowed money. That's the financing-cost effect.

Real estate is the headliner. Few people buy a home with cash and zero loan. But when rates rise, the interest on that loan rises right along with them. Say you borrowed 300 million won and the rate climbs from 3% to 6% — your annual interest burden doubles, from 9 million won to 18 million won. With the monthly payment jumping like that, demand for the same home shrinks, and price gains run out of steam.

Companies are no different. To build a factory or fund a new venture, firms borrow too. When borrowing gets expensive, they scrutinize much harder whether "this project's return actually beats the interest," and the marginal investments — the ones hanging by a thread — get postponed or scrapped. As business activity slows, earnings expectations cool, and that feeds straight back into stock prices.

In short, the financing-cost effect bites hardest on assets that run on debt. Real estate, heavily indebted companies, anything that leans on leverage — they all jump higher whenever rates so much as twitch.

Why Bonds Go the Opposite Way from Rates

"When rates rise, bond prices fall." First time you hear it, you wonder if someone said it backward. But once this one clicks, all three effects above snap into place at once.

A bond is a promissory certificate: "I'll pay you a set interest on set dates." Say you hold one with a 1,000,000 won face value that pays 30,000 won (3% a year). Now market rates rise, so freshly issued bonds pay 50,000 won (5%) on the same 1,000,000 won.

In that instant your 3% bond loses its shine. Who pays full price for a 3% bond when a new 5% one is sitting right there? So to sell yours, you have to mark the price down. The interest it pays (30,000 won) is fixed, so a buyer only matches the new 5% yield if they can grab your bond cheaper. Bottom line: when rates rise, existing bond prices fall; when rates fall, existing bond prices rise. The two move in opposite directions, like a seesaw.

And this seesaw is really the same discount-rate story from before. A bond's price is also "the present value of the future interest and principal you'll receive, added up," and when the discount rate (the market rate) rises, that sum shrinks. Bonds show this relationship most cleanly, which makes them a perfect place to start when you're trying to understand the link between rates and prices.

How Policy Rates, Inflation, and Market Rates Connect

Last, let's string together the words you keep hearing in the news. We've been lumping it all under "interest rates," but there are actually a few distinct kinds.

The policy rate is the rate the central bank sets — literally the benchmark for every other rate. When prices rise too fast (inflation), the bank raises it to cool the economy; when activity sinks too low, it cuts it to loosen money.

Prices are usually measured by the Consumer Price Index (CPI), a number that captures how much the cost of a basket of goods has risen. When prices climb steeply, the central bank tends to lean toward pushing the policy rate up, deciding it "can't let this continue."

Market rates are the rates that form in real transactions — deposits, loans, bonds. The policy rate is the starting point, but market rates move a little differently depending on expectations and supply and demand. Strung together in one line, the flow looks like this:

1. Prices (CPI) rise → the central bank becomes more likely to raise the policy rate
2. The policy rate rises → market rates on deposits, loans, and bonds generally follow upward
3. Market rates rise → the discount, opportunity-cost, and financing effects kick in and press down on asset prices

Of course, reality doesn't march neatly in that order. Markets often jump ahead, betting on "where rates are headed." So prices can wobble before an announcement, then go quiet when the announcement matches what everyone already guessed. Still, keep the chain "prices → policy rate → market rates → asset prices" sketched in your head, and the rate stories in the news will read far more clearly.

If you want to build a feel for rates and prices firsthand, try PriceGuess's price-guessing games and bump into how various assets moved under different conditions yourself. There's no faster way to develop intuition than guessing the numbers on your own.