As the spotlight shines on Carlos Alcaraz's title defence and Novak Djokovic's pursuit of a record 25th Grand Slam, a determined group of challengers is quietly preparing to shake up the draw.
According to a UN report, people live long, healthy lives in these 12 countries.
Singapore retains the title of the world's most expensive city.
Qatar is the world's richest country in terms of per capita income.