Over €80 million in Maltese lira notes and coins have still not been exchanged for euro, two years on from the introduction of the European single currency.

Figures obtained from the Central Bank show that €58.2 million in Maltese notes and €25.6 million in coins remain in people's pockets - or under mattresses.

In November 2008, around €90 million in Maltese notes failed to be returned, which means only around €6 million of the old currency trickled back into the CBM's coffers in the last year. No coins have been handed in since then.

A bank spokesman told The Sunday Times that, given that the deadline for exchanging the remaining Maltese coins in circulation was January 31, it was unlikely that the majority would be presented for redemption at the Central Bank by that date.

Until the end of January, coins are exchangeable only at the Central Bank Annexe, St James's Counterguard, Valletta, from Monday to Friday between 8.30 a.m. and 1 p.m.

The Central Bank will continue to exchange Maltese lira banknotes until January 31, 2018.

In an interview last year, Central Bank governor Michael Bonello said experience suggested there was always a considerable proportion of currency which would never be returned. Some of the higher denomination notes might still be stashed away, and maybe even forgotten.

Given the scale of the tourism industry in Malta, there is probably a significant amount of money that is simply lost. This has been the case in some other countries that introduced the euro - in Ireland and Slovenia it amounted to 15 per cent.

Another contributory factor could be because Malta traditionally has about three to four times the amount of cash in circulation per capita compared with the EU average.

Malta introduced the euro on January 1, 2008, following an intensive campaign to convince hoarders to exchange their cash for the new currency.

The Central Bank said it was not in a position to provide comparable figures to other countries that have introduced the euro.