People all over the world are living longer due to improvements in lifestyle standards and better healthcare. The average life expectancy in almost every country has increased over the last several decades, reaching up to about 90 years old in Monaco, according to the CIA World Factbook. 

Other rankings, such as those by the World Economic Forum (WEF) that look at the general health of populations, provide an understanding into where and why people live the longest.

There are five cities where people live measurably longer lives, popularly known as the Blue Zones. From Ikaria, Greece to Nicoya, Costa Rica, years of investigative research has helped to identify the daily habits and diets of people who are living to an age of 100 at a rate 10 times greater than in the United States. But these five locales don’t make up the entire list.

In general, the more developed a country is, the longer its residents are expected to live. But climate, diet and life choices are other factors significantly contributing to how many birthdays people get to celebrate. The secrets to longer lives also include healthy and happy social relationships where older people feel appreciated.

Where do the world's oldest humans live? Check out the full list of countries.

So which countries get all that right, and where is becoming a centenarian is hardly news?