It is the ultimate snapshot of the state of the nation at the end of the 20th century, and it shows that Britons are living longer, becoming richer and even enjoying better weather.

Britain 2000, the official yearbook of the United Kingdom, published by the office of national statistics, details every aspect of British life from the broad brush of government policy to the number of listed garden sheds, pigsties and lavatories.

The book was devised 51 years ago as a handy reference guide for British diplomats abroad, and every year 10,000 copies are bought by the foreign and commonwealth office and sent to the nation's outposts abroad to be given away to foreign officials and dignitaries. But this year the handbook has been published early in the hope that the general public, caught in a millennium frenzy, will buy Britain 2000 in their hordes as a lasting record of the final year of the century.

John King, the editor of the book, which retails for £37.50, said the millennium was a defining moment.

"This yearbook will be used this time round as a source book for those who want to know what happened at the beginning of the century," he said.

In a break from the norm, the statisticians who have compiled the handbook have also dredged through records from the turn of the century to compare life today with Britain 100 years ago.

The most dramatic change they have identified is that the nation is in the midst of a serious ageing problem. In 1901 the average man lived to 45 while women could expect to last until the ripe old age of 49. Ten decades later and the figures have shot up to 74 and 79 respectively, with the proportion of the population aged 50 and over nearly doubling from one in six in 1901 to about one in three by 1998.

Gordon Brown's pledge to give free television licences to the over 75s could be a lot more expensive over the next two decades than the chancellor might have imagined. There has been a big increase in the number of people living into their 80s and beyond, with projections indicating this group will make up 5% of the population by 2021.

At the other end of the spectrum the number of people under 16 has been falling to such an extent that by 2021 there will be more people aged 65 and over than children under 16.

The armed forces have also changed dramatically in character since Britain was at the peak of its imperial power. In 1900 the Royal Navy had 112,000 officers and seamen, a number that has been reduced to 43,700 in the intervening years.

Meanwhile the army, which totalled 726,000 men here and abroad in 1900, was less concerned with recruiting young offenders as it was about purchasing the 470,000 horses and 150,000 mules and donkeys needed for the Boer war.

Not surprisingly the economy has also seen wholesale changes. At the turn of the century Britain was principally a manufacturing nation, with almost a million people working in the mines and the same number employed in the textile trade. Now there are only 15,000 mineworkers and 160,000 textile workers, while only a quarter of national wealth is generated by manufacturing.

The book even points to evidence of climate change. During the winter of 1899-1900 workers spent more than 55,000 hours removing snow from the streets of Wandsworth alone. In recent years snow has rarely settled for long enough in central London to warrant removal.

Britain's vital statistics

• Just over 6% of the population describe themselves as belonging to a non-white ethnic group.

• The top free tourist attraction in 1998 was Blackpool Pleasure Beach with 3m visitors.

• Some 43,000 people fall from ladders each year, while another 500 burn themselves on barbecues.

• Among sites listed by the government as being of historical importance are 52 garden sheds, 499 pigsties, and 277 lavatories.

• In the past year, the rarest frog in the UK, the European pool frog, has been found in a suburban garden; the glutinous snail, thought extinct, has turned up in north Wales; and the rare allis shad has been caught in the river Tamar, 121 years after it was last recorded.

• Emissions of carbon dioxide from transport have doubled in the past 30 years, while industrial emissions have halved.

• The average income has doubled in real terms between 1971 and 1997.