David: Income without wealth · Money, Explained From the Inside

Meet David

“I earn well. So why does every month end the same way?”

David earns well and spends nearly all of it. There is a car loan, a card balance that never seems to shrink, and almost nothing set aside. Nothing is going badly wrong, and yet nothing is building. His situation is the clearest picture of the difference between income and wealth.

The situationEarns $5,000 a month · Little saved · Car loan · Card debt
The decisionWhere should the next dollar go: down the card, the car loan, or into a first buffer? And is the car itself the problem?
David’s toolsRate translator, True cost of a loan, The minimum-payment trap, Debt payoff planner, Borrowing capacity & debt-to-income

The portrait and the quoted line are illustrations written for this companion. Situations follow the book; figures on this page are modelling assumptions.

Explore the numbers

Work through the case, step by step

Each step uses a tool with David’s situation already filled in. Change any number to see another outcome.

See the pictureIncome is not wealth

David’s numbers. Modelled for this case, ready to change.

Start where David would: what comes in, what is already spoken for, and what he owns and owes.

Monthly margin: $200.004% of take-home pay
Net worth: -$9,500Assets $10,500 − liabilities $20,000
Committed share: 66%The part of your pay that is spoken for before the month begins.
Everyday share: 30%

What this means

A good income with a thin margin is still fragile. A modest income with a steady margin compounds into wealth. Margin is what turns income into net worth.

A negative net worth is common early on, especially with student or car debt. The direction of travel matters more than the starting point.

Notice: A comfortable income, a thin margin and a negative net worth: that is “income without wealth”. Try a different mix of commitments.

Open the full “Margin & net worth” page: formula, worked example and cautions →

The cardA balance that outlives its purchases

David’s numbers. Modelled for this case, ready to change.

The card is not large, but it is expensive. What does paying only the minimum do?

Minimum payments only: time to clear: More than 100 years
Minimum payments only: interest paid: $144,000
First month’s minimum: $120.00
Paying that same amount every month: Never clearsThe payment is smaller than the monthly interest.

Years on the horizontal axis.

Minimum payments only

What this means

When the minimum is a percentage of the balance, it shrinks as you pay. The payment falls as fast as the debt, so the debt lingers for years.

The simplest escape is to fix the payment at today’s minimum, or more, and never let it fall.

Notice: Fix the payment instead of letting it shrink and watch the years and the interest fall away.

Open the full “The minimum-payment trap” page: formula, worked example and cautions →

The orderWhich debt first?

David’s numbers. Modelled for this case, ready to change.

David can put a little extra toward his debts each month. The order matters.

Avalanche: debt-free in: 2 yr 5 mo$3,039 interest
Interest saved vs minimums: $4,895
Payoff order (avalanche): Debt 1 → Debt 2

Years on the horizontal axis.

Avalanche
Snowball
Minimums only

Strategy	Time to clear	Total interest
Avalanche (highest rate first)	2 yr 5 mo	$3,039
Snowball (smallest balance first)	2 yr 5 mo	$3,039
Minimums only	6 yr 10 mo	$7,934

What this means

The avalanche always costs the least interest. The snowball sometimes costs a little more but delivers the first “paid off” sooner. The best plan is the one you will actually follow.

Notice the gap to “minimums only”: it is mostly the effect of paying a fixed total each month, not of the ordering.

Notice: The expensive card comes first even though the car loan is larger. The rate, not the size, sets the order.

Open the full “Debt payoff planner” page: formula, worked example and cautions →

The loanHow was the car loan really priced?

David’s numbers. Modelled for this case, ready to change.

Suppose the dealer quoted it as a low “flat” rate. What would the cost look like?

Monthly payment: $309.17
Total cost of credit: $4,850Interest plus fees
Total you repay: $18,550
Effective annual rate (with fees): 13.4%Quoted: 6.50% flat
Same loan as a reducing-balance rate: 11.7%Before fees. The number to compare with other offers.

Months on the horizontal axis.

What you actually still owe
What flat interest is charged on

What this means

A flat rate charges interest on the full amount for the whole term, even though you are repaying it month by month. That is why “6% flat” behaves like a loan at roughly twice that rate.

Fees paid up front lift the effective rate because you receive less than you owe. Compare offers on total cost of credit and effective rate, not on the payment.

Notice: Switch “flat” to “reducing” and see what the same headline rate means. Ask which one you are being quoted.

Open the full “True cost of a loan” page: formula, worked example and cautions →

The carWhat the car really costs to own

David’s numbers. Modelled for this case, ready to change.

Beyond the loan, a car has running costs and ties up money that could be working.

Cash cost over the period: $36,900$6,150 a year
Including opportunity cost: $7,840a year
Value recovered at the end: $6,300
Opportunity cost alone: $10,139Growth forgone on the money tied up

What this means

Think of the yearly figure as the rent you pay to own the thing. Compare it with alternatives: a cheaper model, an older one, or not owning at all.

Running costs usually decide the total more than the price does.

Notice: The yearly figure is the rent David pays to own it. Is it worth that?

Open the full “True cost of owning” page: formula, worked example and cautions →

The figures on this page are modelling assumptions chosen for this companion to illustrate the situation. They are not quoted from the book, and are not personal advice. Change every one.

The lesson

Income buys a lifestyle; margin buys a future. David’s way out is not a bigger salary but a larger gap between what comes in and what is already spoken for, and a deliberate order for the debts that are quietly taxing him.

In the book: Ch 1: The Language of Money · Ch 6: Your Personal Financial System · Ch 11: The True Cost of Borrowing · Ch 12: Credit Cards, Overdrafts and Revolving Debt · Ch 14: Making Debt Decisions

Now your turn

Apply the same idea to you

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David34

Work through the case, step by step

What this means

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Apply the same idea to you