When averaging it out over 150 years, the USA growth rate is ~2% p.a. The USA's secret is managing to have stayed stable enough over that period, and having ma

When averaging it out over 150 years, the USA growth rate is ~2% p.a. The USA's secret is managing to have stayed stable enough over that period, and having maintained that growth number. No-one can sustain 8-10% indefinitely, once the "easy" growth (industrialization, infrastructure, education, urbanization) is in the bag.