Why does my country's per capita income account for a much smaller proportion of per capita GDP than the United States?

Personal consumption accounts for a smaller proportion of GDP in China, but there is absolutely no gap between 50% and 80%. Large investment is one thing, but the most important thing is taxation.

Personal income tax in the United States accounts for a large part of the tax revenue, and those with high incomes will pay nearly half of the tax. The per capita income you mentioned in 2006 was US$36,276. The per capita income here should be before tax. Personal income tax in China is very small. I heard that only 30% of people pay personal income tax. China's tax VAT accounts for a lot.

In 2006, the U.S. GDP was 13.2 trillion, and government spending was already 2.5 trillion, accounting for 19%. And that’s not counting investment. The net exports of the United States in 2006 were negative 0.7 trillion, so personal consumption and government investment = 13.9 trillion, which is slightly higher than GDP. Personal consumption cannot be 86% of GDP.