Royal Mail today reveals why your postcode is so unforgettable. New research shows that over nine in ten (92%) of Brits find it easier to remember their home postcode, than their wedding anniversary (46%), their parents’ or child’s birthdays (66%) and their debit card pin numbers (77%).
The easiest personal information to remember was:
- Home postcode (92%)
- Debit card pin numbers (77%)
- Home phone number (73%)
- Personal email passwords (70%)
- Personal mobile number (67%)
- Parent’s/children’s birthdays (66%)
- Partner’s birthday (63%)
- Online banking passwords (57%)
- Credit card pin numbers (51%)
- Personal mobile phone pin/passcode (49%)
Postcodes were originally trialled in Norwich over 57 years ago as part of a major mechanism programme. Since then, they have become an essential part of everyday life. So much so, that we now struggle to forget them. According to a separate study, just under one in five (17%) are able to recite the postcode of the home they lived in 21-30 years ago with a quarter (24%) reeling off the postcode for the fifth home they lived in before their current abode.
Design of the postcode
Leading memory expert, Professor Alan Baddeley CBE, FRS, FBA, FMedSci, was part of a team of psychologists who worked to develop the design of the postcode in the late 50s. The team, led by Dr R. Conrad who becomes a centenarian this year, opted for a mix of digits and letters.
Professor Baddeley explains: “The immediate memory span is typically around six or seven items so we examined a range of designs based on this size. Pure number codes proved hard to remember and each digit had a smaller range of permutations (10 per digit). Letters, on the other hand, had 26 permutations per letter in line with the alphabet. This allowed a short and memorable code that would sort to street level.
“We selected a mixture of letters and numbers and added to its memorability by starting, whenever possible, with the initial letters of the town name, e.g. NOR for Norwich. This meant that the most important part of the code is upfront so that if any errors were made in the harder part, the item would at least arrive in the correct area.
“The second part used a digit and two letters, giving a large number of possibilities (10 x 26 x 26). We slotted the number in the middle because as the odd item among letters, it stands out and assists recall at the point where errors are most likely to occur.
“We are pleased that the postcode has proved to be so memorable and amazed that it has become so widely used. Originally it was used purely as a mail sorting tool but is now used to do hundreds of things from finding directions to buying items online and even confirming your own identity over the phone.”
History of the postcode
The UK was the first country in the world to introduce the idea of a postcode. In 1838, Rowland Hill suggested dividing London and Greater London into districts to speed up the delivery of mail. This was done by splitting the city into ten separate districts, denoted by compass points: EC (Eastern Central District), WC (Western Central District), and NW, N, NE, E, SE, S, SW and W. The public were implemented in 1857-58 and are the basis of the London and Greater London districts we know today.
Postcodes were introduced nationally in 1959 so that machines could sort mail quickly and efficiently. The use of machines required that addresses were translated into a short readable code. In 1966, the eight-year programme to postcode the whole country began. This was completed in 1974 with the recoding of Norwich.
Britain is one of only seven post coding systems in the world that uses an alphanumeric system – a combination of letter and numbers. This allows a greater number of unique combinations to be used – over 48 million. Today there are around 1.8 million postcodes in use across the country covering over 29 million addresses including a number of iconic landmarks (SW1A 1AA – Buckingham Palace), sporting venues (SW19 – Wimbledon) and even the nation’s favourite soap operas (the fictional postcode E20 for Albert Square, Eastenders, which later transferred to the Olympic Park).
Steve Rooney, Head of Royal Mail’s Address Management Unit, said: “The introduction of the postcode over 50 years ago marked the start of consumers using technology as a part of their everyday lives.
“When the concept was originally being explored the iconic combination of letters and numbers was chosen as people could remember it more easily than a list of numbers. No-one would have ever thought that over the last five decades it would have evolved from being a mechanism for posting mail to becoming an integral part of modern life.”