Korea's Doubling Money Supply: Why a 7% Annual Return Just Breaks Even

Your bank account balance may have nudged slightly higher than last year, yet the number of items in your grocery cart has actually shrunk. While it is easy to dismiss this experience as a matter of personal spending habits, it is highly likely a structural transformation taking place far beyond individual control. The total amount of money circulating across the nation continues to expand relentlessly. Why, then, does money keep increasing, what exact outcome unfolds if you fail to match that pace, and what concrete steps must an individual take to keep up?

The True Meaning Behind Money Supply Doubling Every 10 Years

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The bottom-line conclusion of this story is that standing still demotes you down the wealth hierarchy. In the lecture video "Financial Studies That Make You Money Even If You Know Absolutely Nothing | Lee Jin-woo's Economics Master Part 1" on the EBSCulture channel (https://www.youtube.com/watch?v=45BACPG6jPQ), the 1-hour 31-minute session is divided into three pillars: money supply, risk, and interest & exchange rates. Among the three, the most valuable part is the first. This is because rather than delivering generic investment methodologies, it explains why investing is mandatory using a single decisive figure.

The lecturer cites the liquidity of financial institutions tabulated by the Bank of Korea as primary evidence. As of the summer of 2024, it stood at approximately KRW 5,500 trillion; 10 years prior, it was roughly half that at around KRW 2,700 trillion; and 20 years prior, it stood at roughly half again, approximately KRW 1,250 trillion. If this trend of doubling every 10 years continues unabated, an estimate follows that it will exceed KRW 10,000 trillion (10 quadrillion won) a decade from now. The deduction derived here forms the core axis of the entire lecture: If circulating broad money doubles in 10 years while your assets remain flat, your absolute balance may be unchanged, but your relative share of the overall pie shrinks by half.

The compelling strength of this logic lies in redefining wealth building not as greed, but as defense. The speaker uses the phrase that we live in an era where investing exceptionally well merely allows one to break even. It represents not a discretionary choice to acquire more, but a maintenance cost required simply to prevent falling behind. Compared to the bulk of wealth-building content that opens with enticing returns or success stories, the departure point itself is entirely different. It is also pragmatic in offering a baseline for calculations. Doubling over 10 years translates to roughly a 7% compound annual growth rate, and the lecturer likewise states that around 7% annually represents the waterline for preserving one's relative wealth standing.

Three Faucets Producing Money: Commercial Banks Are the Thickest

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The conduits through which money increases are summarized into three channels. The first is commercial banks, the second is the Bank of Korea (central bank), and the third is incoming foreign dollars. Among these, commercial banks constitute the thickest pipe.

The most counterintuitive explanation in the lecture appears in the section on commercial banking. The conventional wisdom that banks lend out money deposited by savers is factually incorrect. Banks do not open their vaults to check for physical cash before disbursing loans; rather, upon evaluating a borrower's creditworthiness, they simply type numbers into that person's account ledger. And those recorded digits instantly become new deposits. The moment a loan is granted, an identical sum of deposits is birthed simultaneously, meaning that structurally, banks face no shortage of funds. The proof presented is that no customer at a loan desk has ever heard a teller say that the bank ran out of prepared money for the day. Ultimately, every time a bank approves a loan, the total money supply in the world expands by that exact amount.

The second channel, the Bank of Korea, functions bidirectionally. Up to the point where the government issues treasury bonds to cover tax revenue deficits, aggregate money supply does not expand—funds merely circulate from the private sector to the government. Money is newly created the moment commercial banks take those government bonds as collateral to obtain central bank liquidity. The third channel, foreign capital inflow, behaves similarly. When foreigners bring in US dollars and convert them into Korean won, new won liquidity is injected; when they convert won back into dollars to exit, that money disappears. Examining these three conduits reveals that none can be effortlessly turned off. One only needs to imagine scenarios where banks stop issuing loans, the government spends strictly within actual tax collections, or trade surpluses vanish completely. Here lies the reason why the projection that money supply will continue to expand remains thoroughly convincing.

Flaws in the 7% Benchmark

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While a 7% annual return is convenient to adopt as a personal target, taking it at face value leaves noticeable rough edges. The biggest issue is that an aggregate macroeconomic metric like broad money supply is directly translated into an individual's required rate of return. Money supply represents a macro total inclusive of credit generated through debt, and that money is not distributed uniformly among 50 million citizens. Freshly minted money flows first toward those capable of borrowing—namely, those who already possess collateral. The village anecdote shared in the lecture demonstrates this exact reality: money was granted to the second son who possessed a house to pledge as collateral. Those without pre-existing assets fall behind far more rapidly during phases of monetary expansion. This leads to the deduction that the required return for asset-poor individuals must be substantially higher than 7%, a critical point the lecture leaves untouched.

The omission of taxes and friction costs also warrants examination. A 7% annual return is a nominal figure, whereas the money that actually stays in hand is whatever remains after deducting capital gains taxes, transaction fees, and management expenses. To preserve a net 7% after taxes, gross returns must be considerably higher. Even more regrettable is the absence of any discussion on how to amass initial investment capital. The proposition that assets must match the growth velocity of money supply is an actionable guideline exclusively for those who already possess seed money. The crux of the challenge is that wage growth does not compound at the speed of broad money, yet after pointing out this systemic hurdle, the lecture pivots solely toward investing as the panacea.

A conflicting element within the lecture also emerges. The speaker shows how a chart starting from 1986 and another starting from 1990 yield completely opposite conclusions, demonstrating that a single starting point can dictate all subsequent track records. This is an excellent insight. Yet later on, the speaker presents a statistic claiming that holding the KOSPI for 5 years yielded positive returns with a 93% probability. Applying the prior logic to this subsequent statistic means that the 93% figure is likewise contingent on which historical timeframe was clipped and measured. The speaker emphasizes the decisive power of starting points, yet fails to apply the exact same critical standard to their own statistical claim.

Volatility Directly Erodes Compounded Returns

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The intuitive feeling that making large gains and suffering large losses balances out to break-even is completely wrong. The calculation presented in the lecture head-on dismantles this illusion. If KRW 100 million is invested over 4 years moving +20%, -10%, +20%, and -10%, it turns into KRW 116.64 million. If the same principal experiences +50%, -40%, +50%, and -40% over 4 years, it actually shrinks down to KRW 81 million. Even though the latter gained far more during winning periods, it ended up eroding principal. High volatility does not merely widen the swing between profits and losses; it drags down the terminal compounded outcome itself.

Here, the lecture proposes distinguishing between risk and danger. A game where a single outcome determines bankruptcy constitutes danger, whereas an arena broken down into multiple iterations where statistical probabilities can play out represents risk. A coin-toss game wagering KRW 500 million against KRW 1 billion should never be played even if winning probability is 50%, whereas dividing that identical game into 100 installments of KRW 5 million completely transforms its nature. The practical takeaway of this distinction is unambiguous: Preventing irreversible drawdowns takes precedence over maximizing nominal returns.

However, the prescription to increase frequency and hold over longer periods must come with qualifications. For a time-horizon expansion strategy to hold, an investor must be able to endure without selling throughout the drawdown, and whether one can endure is dictated by cash flow, not psychology. If a jeonse deposit must be topped up, children's tuition comes due, or loan principal repayments approach, an investor will be forced to liquidate at market bottoms regardless of theoretical probabilities. While the lecture frames maintaining a cash buffer as a psychological stabilizer, it is far more accurately viewed as a liquidity safeguard that prevents involuntary selling. An investor who can withstand 5 years and one who cannot are fundamentally playing two different games.

Overall Assessment: Agreement on Diagnosis, Conditional Agreement on Prescription

The point of agreement rests on how the mechanics of monetary expansion are dissected. The explanation that deposits are created the moment a bank approves a loan, and the diagnosis that the three conduits—banks, the central bank, and foreign capital—cannot be easily shut off, illustrate through real mechanisms why money supply inevitably grows. Under this structural reality, holding onto pure cash is functionally equivalent to taking a loss. With aggregate money supply doubling every 10 years, the calculation showing that doing nothing reduces one's relative share of the overall economy is impossible to refute.

Reservations concern the 7% annual benchmark and the prescriptions given to execute it. Because this figure directly transplants a macro aggregate metric onto an individual, it does not carry equal weight for someone with existing collateral assets versus someone with none. The lecture also bypasses the fact that pre-tax returns must be substantially higher to secure a 7% net gain after taxes and friction costs. For an individual starting without capital, the required hurdle rate is not 7%, but a considerably steeper figure. Similarly, the approach to managing volatility operates differently across individuals. In an identical bear market, someone who has set aside several months of living expenses and someone facing immediate cash deficits have entirely different survivable horizons, and that divergence dictates the ultimate outcome.

3 Actionable Steps to Take Today

1. Compare the interest rate on your active debts against the 7% target return.
2. Isolate and secure several months of living expenses completely separate from investment funds.
3. Instead of deploying remaining capital all at once, dollar-cost average by splitting purchase timings and targets.

While an individual cannot alter the macro trajectory of expanding money supply, you can control the velocity at which your own assets move along that tide. However, rather than adopting a flat 7% return as a universal benchmark, the proper sequence begins by writing down your personal debt interest rates and how much survival cash you have on hand.