I have a noob question. How can developed economies where populations levels have plateaued continue to be expected to post positive GDPs (and therefore add net new goods and services) yoy?

Homes as assets should pass on, higher cost services of today would be replaced by lower cost which only temporarily would increase units sold(but should eventually plateau because #units/person is not going to change). No component of the GDP will move.

If the fertility rate of developed economies is less than 2.1 then there should be wealth and asset accumulation among the younger people over time. The demand for newer goods and services from the people who get richer is inelastic: most goods and service's prices dont matter to the rich they buy them any ways, and it continues to keep becoming more inelastic.

So within like a several years the demand should just collapse as wealth accumulates a lot and people work less and become more price insensitive. Immigration is set to remain low to developed nations for the next 3-5 years.

This seems to be quite evident in Japan and EU already(though in the EU if you adjust the productivity for work hours the GDP becomes same as America's).

So why do people assume developed countries would even buy this much more new stuff. 1.5 trillion$ worth of new things over the next 5 years?

GDP does not require that the goods or services were sold for money. GDP measures the market value adjusted to constant quality of all final goods and services produced. GDP can grow even with fewer workers, fewer hours, fewer buyers, and fewer units sold.

So the way I understood it, productivity, efficiency and quality gains can increase GDP year over year.

Say we are a country of 1 person. If that person can make a car in 2025, but in 2026 manages to make both a car and a house, the GDP has more than doubled. Doesn't matter that nobody paid the money for them.

Another weird thing is, say that 1 person country makes a car in 2025, and in 2026 makes a similarly priced car, if the car is higher quality, it counts as a higher GDP, because they'll measure its value as greater than last year's model, even if it sells for the same price, because the old model would now be worth less.

Maybe because the advertising and marketing machine will continue to churn and induldge and shame people into consuming ever more stuff.

> How can developed economies where populations levels have plateaued continue to be expected to post positive GDPs (and therefore add net new goods and services) yoy?

Think about the unsatisfied needs and desires most people have. In extremely low income areas, it may be a roof over your head or knowing where your next meal comes from. Moving up a tier, it might be the ability to send your children to education or better clothing. In wealthier areas it might be things like a better car or higher quality food even though you're not in danger of going hungry. For the extremely wealthy it might be more leisure time, art, and new experiences.

When GDP increases, broadly, those are the areas you see expand. Looking at life today in a baseline American household, the things which are mass produced are far more available and affordable than they were a century ago - in the 1930s households spent about 10-12% of their income on clothing.

Sadly, the rate of improvement for non-mass-produced items like college tuition, medical care, and especially housing has ballooned compared to median income, so life doesn't feel inexpensive, certainly, but GDP has a lot of room to grow in a lot of areas.

People don't stop wanting things.

Total GDP can keep rising so long as technologist can improve efficiency through robotics, inventions and scientific breakthroughs.

GDP just describes peoples amount of activity. People will always build bigger buildings or monuments (see egypt pyramids, dubai skyscrapers, cambodia angkor wat). These are actaully not inelastic as megaprojects will quickly hit real limits regardless of the amount of capital. (I can always add 10 more floors to the tallest skyscraper, or 10 feet to the longest wall, or 10 facets to the most ornate church)

There has never once in history been a point where people decieded that they where going to stop innovating or producing permanently. This is equivalent with death.

So the people with the most money at some point will decide to build things which they spend all their money on which increases GDP.

Also the actual "number" of gdp if heavily controlled by USA inflation rates. So we should always look at gdp in regards to inflation adjusted dollars to get a clearer picture.

Think of GDP as a country’s output.

Your entire premise is simply incorrect, through and through. Discard it entirely and begin again.

You have a hundred people, they have a GDP of N. Tomorrow, their productivity doubles because of a technological innovation. Your GDP is 2N.

Prices matter extensively to the rich and poor. The cost of a given compute capacity has gone from "literally the entire United States can't afford it" to "my lightbulb has this much compute because it's cheaper than choosing a dumber processor".

What happens tomorrow if eg ChatGPT 5.1 performance becomes doable for $500 of tech? $50? Swap this for grain harvesting, waste bin collection, etc if you don't like the LLM case.