The fund, which is now equivalent to 8.9% of Portugal’s gross domestic product (GDP), incorporates transfers of surpluses from the country’s social security system, which in 2018 amounted to €1.5 million.

An official at the ministry told Lusa that the large size of transfers to the FEFSS in recent years "reflects the government's commitment to strengthening the sustainability of social security."

Several factors have contributed decisively to the boost to the fund in recent years, including the creation of alternative sources of financing, such as a surcharge on the Municipal Tax on Property (IMI) - created in 2017 and which focusses on properties owned by companies that are not used for their official activity and on properties owned by individuals that are worth more than €600,000 – and a slice of revenue from corporate income tax (IRC). Together, these made it possible to channel €170 million to the FEFSS.

Other factors that contributed to swelling the fund include the increase in the value of assets, which, according to the same official source, was around €1.167 billion in three years.

Between the end of 2015 and the end of 2018, the value of the FEFSS value increased by approximately €3.3 billion.

The recovery of Portugal’s labour market, with the decline in unemployment, the increase in employment and wage rises have, in the meantime, had a positive impact on the growth of social security contributions.

In January contributions and levies increased by €229 million on the same month of 2018, or 8.3% - the largest year-on-year increase since 2001.