According to the United Nations-backed Global AgeWatch Index 2013, Sweden is the best place to grow old, and Afghanistan is the worst — with the U.S. in 8th place following New Zealand and Switzerland.

The study, led by the HelpAge International advocacy group and the UN Population Fund, aimed to tap into an issue that is expected to gain importance in coming years — taking care of a graying generation. The number of senior citizens will rise in the next 40 years, from about 809 million in 2013 to more than two billion in 2050.

"The 21st century is seeing an unprecedented global demographic transition, with population ageing at its heart," the authors of the study said.

HelpAge International is running an Age Demands Action (ADA) campaign, which calls on leaders to make decisions on health care and pensions that will benefit the quality of life for the world's geriatric population.

The survey reviewed social and economic factors surrounding people over 60 in 91 different countries, including their incomes, education, health, employment, and environment. Sweden has had a universal pension system for a century, and Norway, which ranked 2nd, brought in a pension system in 1937.

While it may have been expected that low-income countries would be ranked lower on the scale, it turns out that certain countries like Bolivia were singled out for offering free health care to older citizens. Sri Lanka, meanwhile, had also put into place long-term investments in health and education.

"By giving us a better understanding of the quality of life of women and men as they age, this new index can help us focus our attention on where things are going well and where we have to make improvements," HelpAge’s chief executive, Silvia Stefanoni, said in a statement.

Find the full list of countries here.