Countries in the top quartile of freedom have a much higher average per capita income than those in other quartiles

See An Update on the Global State of Human Freedom by Marian L. Tupy.

"As Editor of Human Progress, I have the pleasure of writing about the improving state of the world. Evidence from individual scholars, academic institutions, and international organisations clearly shows that human conditions are improving – especially in developing countries.
As Steven Pinker, the Johnstone Professor of Psychology at Harvard University writes in his upcoming book, Enlightenment Now: The Case for Reason, Science, Humanism, and Progress, “The world has made spectacular progress in every single measure of human well-being.”
Regrettably, progress is not linear and the occasional backwards step is unavoidable. Just think of the two World Wars and various genocides that scarred the 20th century. But, to quote Kevin Kelly, founding Executive Editor of Wired magazine, “Ever since the Enlightenment and the invention of Science, we’ve managed to create a tiny bit more than we’ve destroyed each year. But that few percent positive difference is compounded over decades into what we might call civilization.”   
Moreover, progress is not guaranteed. The world could experience a nuclear conflict or an asteroid strike – either of which has the potential to wipe us all out. Not all threats are existential, of course. In recent years, for example, we have witnessed a sustained attack on political and economic freedoms, as well as freedoms of religion and free expression. Considering that human freedom is an integral part of human progress, these particular developments are worth exploring in greater depth.

The Cato Institute’s Center for Global Liberty and Prosperity, where I work, has been measuring the state of human freedom since 2008 – a veritable annus horribilis that saw the greatest economic crisis since the Great Depression, and gave rise to a range of populist movements and illiberal policies. The 2017 Human Freedom Index, published today, once more observes a general decline in human freedom.
How do the reports authors define freedom? “The contest between liberty and power has been ongoing for millennia. For just as long, it has inspired competing conceptions of freedom,” write Ian Vásquez and Tanja Porčnik, who produced the study. “Freedom in our usage is a social concept that recognizes the dignity of individuals and is defined by the absence of coercive constraint … Freedom thus implies that individuals have the right to lead their lives as they wish as long as they respect the equal rights of others.”
This definition of freedom will be familiar to all those who are aware of Isaiah Berlin’s notion of negative liberty. “In the simplest terms,” the authors note, “negative liberty means noninterference by others. Berlin contrasts that type of liberty with positive liberty, which requires the removal of constraints that impede one’s personal improvement or the fulfillment of his potential as the individual understands it.”

Since negative liberty “comes in only one flavor — the lack of constraint imposed on the individual,” it is more easily measured. As such, the HFI uses 79 distinct indicators of personal and economic freedom in the following areas: rule of law, security and safety, movement, religion, expression and information, identity and relationships, size of government, legal system and property rights, access to sound money, and freedom to trade internationally. It also looks at freedom of association, assembly, and civil society, and regulation of credit, labor, and business.

The 2017 HFI covers 159 countries, with 2015 being the most recent year for which sufficient data are available. On a scale of 0 to 10, where 10 represents more freedom, the average human freedom rating for 159 countries in 2015 was 6.93. Among the countries included in the index, the level of freedom decreased slightly (by 0.05 points) compared to 2014, with 61 countries increasing their ratings and 97 losing ground. Since 2008, the level of global freedom has also fallen slightly (by 0.12 points), with about half of the countries in the index increasing their ratings and half decreasing.

The top five freest jurisdictions are Switzerland, Hong Kong, New Zealand, Ireland, and Australia. The bottom five jurisdictions are Egypt, Yemen, Libya, Venezuela, and Syria. The countries that improved their level of human freedom most since last year’s report are Sierra Leone, Iran, Botswana, Singapore and Suriname. The largest deteriorations in freedom occurred in Burundi, Brunei, Cameroon, Venezuela, and Tajikistan.
Vásquez and Porčnik believe that human freedom and material human progress are related. To give just one example, countries in the top quartile of freedom enjoy a significantly higher average per capita income ($38,871) than those in other quartiles. The average per capita income in the least-free quartile is $10,346. The HFI also finds a strong relationship between human freedom and democracy.

Others may, of course, draw their own conclusions. If, however, all of us agree that freedom is important in and of itself, the slow deterioration of freedom throughout the world is food for thought."