World economic freedom has reached record levels, according to the 2014 Index of Economic Freedom, released Tuesday by the Heritage Foundation and The Wall Street Journal. But after seven straight years of decline, the U.S. has dropped out of the top 10 most economically free countries.

For 20 years, the index has measured a nation's commitment to free enterprise on a scale of 0 to 100 by evaluating 10 categories, including fiscal soundness, government size and property rights. These commitments have powerful effects: Countries achieving higher levels of economic freedom consistently and measurably outperform others in economic growth, long-term prosperity and social progress. Botswana, for example, has made gains through low tax rates and political stability.

Those losing freedom, on the other hand, risk economic stagnation, high unemployment and deteriorating social conditions. For instance, heavy-handed government intervention in Brazil's economy continues to limit mobility and fuel a sense of injustice.

It's not hard to see why the U.S. is losing ground. Even marginal tax rates exceeding 43% cannot finance runaway government spending, which has caused the national debt to skyrocket. The Obama administration continues to shackle entire sectors of the economy with regulation, including health care, finance and energy. The intervention impedes both personal freedom and national prosperity.

But as the U.S. economy languishes, many countries are leaping ahead, thanks to policies that enhance economic freedom—the same ones that made the U.S. economy the most powerful in the world. Governments in 114 countries have taken steps in the past year to increase the economic freedom of their citizens. Forty-three countries, from every part of the world, have now reached their highest economic freedom ranking in the index's history.