Do you know where the six million missing pennies are?

Not only have we been picking up pennies to ensure a little bit of good fortune, we've been keeping them in jars so no one else can have them either. A recent report from the Royal Mint estimates a whopping 6,500 million of them have gone missing since they were introduced 36 years ago.

The penny as we now know it first came into circulation on February 15, 1971. It was one of a trio of copper coins introduced when the country went decimal - the other coins being the halfpenny and the two pence piece.

To avoid confusion between the old and new coinage, all three coins had the word new' incorporated into the reverse design, which was later removed in 1982.

So where are the £65 million worth of missing coins?

No one really knows, but then, if no one really knows, how can we be sure 6,500 million of them are missing? The answer is simple, according to a spokesman for the Royal Mint.

"More than 10,500 million 1p coins are in circulation. That figure, compared with the total number of 1p coins issued since the coin was introduced 36 years ago, suggests in excess of 6,500 million are no longer out there."

The mint reckons travellers taking our pennies out of the country as keepsakes are partly to blame, but it's worth noting, for any holidaymakers who are reading, that taking coins out of the country is technically illegal.

Most of us have a penny jar or, even better, an oversized whisky bottle that's been in the family for years, so we safely account for a large proportion due to hoarding.

While this is far from being illegal, the mint do discourage people from holding onto their pennies, but it is something they take into account.

"It has always been the case that the public collects coins in piggy banks etc," says the Royal Mint. "The Royal Mint responds to demand from the public, issuing 585 million pennies during 2005 and 2006. This shows there is still a demand for the coin."