The effects of the global financial crisis have pushed “supranational” organisations such as the World Bank to issue record levels of debt to investors.

Pan-national borrowers such as the European Investment Bank, World Bank and Inter-American Development Bank have raised $219bn on global debt markets in 2014 – the largest sum raised at this point in a year, according to data from Dealogic.

Ultraconservative investors, including central banks and commercial banks, have fuelled demand for the higher yields and lower risk that their bonds can offer, at a time when the pool of triple-A rated bonds has been contracting. Supranational borrowers are deemed lower risk because of their government guarantees. Their bonds also provide a small yield pick-up over debt issued by individual governments. When the World Bank issued $5bn of debt maturing in May 2016, the yield was about 20 basis points higher than equivalent US government bonds.