If you're a 50-year-old man in New York, $100,000 can buy you monthly income of about $400. You'd come out ahead in 21 years, and all additional income would come at no further cost.

In France, the retirement age for the state pension is 62 for those born in or after 1955. From September, it will rise to 64 for those born in or after 1968. Early retirement is available at age ...