A country with high population growth can make enormous economic stirdes and still lose ground per capita if its population grows faster than its GDP. Also, the whole concept of GDP needs to be seriously rethought. Norway exports oil, and oil technology, but the USA's biggest growth areas recently have been real estate, financial instruments, and services. In other words, nothing of any real value. There has been no real growth, just bogus profit. We produce less and less every year. We're printing money.

Population growth does not drive economic growth, but it does provide the illusion of future markets which will justify growth. The current business model needs the promise of growth to justify the money it borrows to finance future growth. Our system cannot work without constant growth, because it always owes more than it can pay. Nothing grows exponentially in nature, sooner or later the Petri dish gets too crowded and the bacteria die from their own wastes.