Not many pieces of paperwork have the potential to affect where billions of pounds is spent, but the 2011 census does.

Mayor of London Boris Johnson says it is crucial everyone fills in their forms as population data plays a vital role in where funding is distributed.

Mr Johnson says people can improve the next 10 years of their lives in the time it takes to have a cup of tea.

“I want each and every Londoner to complete their census form so that London does not lose out. This research can’t influence this week’s budget, but it will inform the next.

“In large part because of its tremendous diversity London has the lowest response rates in the country. In 2001, the 14 areas of the UK with the lowest returns were all in the capital.

“Did you know that the low response rate in London potentially means up to an estimated �600 is lost in council services for every form left blank, simply because some people think it is an outdated population count they don’t need to worry about?

“Over a quarter of public spending in London - �19.3 billion – is linked to population figures. Your child’s school, your local GP surgery or the bus or tube you travel to work on all end up benefiting from you completing the form.

“In these difficult times when public money is so short it is especially vital that we are able to secure whatever allocation of money for services we are entitled to, to keep Londoners housed, healthy, safe and looked after.

“All Londoners should have received their census form by now. Don’t throw it away; it takes just 10 to 15 minutes to fill it in. A cup of tea and a biscuit later and you’re done. This year you can even do it online. As ever, the information you provide is kept completely confidential.

“Don’t miss out on your chance to ensure a fair deal for yourself and your community. Let’s not lose money that is there and rightfully belongs to Londoners.

“Improve the next 10 years of your life in a teabreak!”