Singapore has achieved the highest tier in the annual global pension system rankings for the first time, while the Netherlands maintains its top position.

In this year's Mercer CFA Institute Global Pension Index, three other countries received A-grade ratings: Iceland, Denmark, and Israel. The report, released on Wednesday, conducted comparative assessments of 52 pension systems across adequacy, sustainability, and integrity dimensions.

Tim Jenkins, a Sydney-based partner at consulting firm Mercer and lead author of the report, stated that Singapore's continuous strengthening of its pension system over the years has driven its global ranking improvement. Recent government initiatives have focused on enhancing transparency to ensure people better understand their retirement benefit expectations.

Singapore's pension system centers on the Central Provident Fund, which covers all employed citizens and permanent residents through mandatory contributions from both employers and employees. In 2009, Singapore received only a C-grade rating in the global index, improving to B+ by last year.

"Singapore's leap from C-grade all the way to A-grade has been supported by the country's economic performance," Jenkins noted, highlighting that the index's sustainability metrics incorporate long-term economic growth considerations.

In this year's rankings, the United States placed 30th, the United Kingdom 12th, and Japan 39th. India ranked last with a D-grade rating, following Argentina, the Philippines, and Turkey, all of which also received D-grade ratings.