The stereotype goes that Germans have to measure and record everything with perfect exactitude. So it comes as a bit of a shock to some that a number as essential as the country's population turned out to be much lower than previously assumed.

With 80.2 million people, Germany remains the largest EU country by a significant margin. However, compared with previously held estimates, that number represents a sudden drop of 1.5 million residents. In a sense, a metropolis the size of Munich now vanished overnight.

The new information comes by way of the 2011 census, for which one third of the total population was polled personally or in writing. The comprehensive survey cost over 700 million euros ($908.6 million). Data collected included marital status, educational attainment, occupation and immigration status. Analyzing the responses took two years, so the recently published results are no longer entirely up to date. Experts believe, however, that the data represent an accurate snapshot of social trends in Germany for the time period in which it was collected.

First census since reunification

There had not been such a thorough collection of census data since East and West Germany were reunited in 1990. Previous estimates were based on a census conducted in West Germany in 1987 as well as another carried out in 1981 in East Germany. Since then, the number of residents was simply adjusted and updated with the help of data on births, deaths and changes of residence.

"Between two censuses, the municipal registries of residents grow less and less exact, and that almost always leads to an overestimate of the numbers because many people register a new residence but never give notice of departure from their previous one," said statistician Gerd Bosbach at the Koblenz University of Applied Science.

Fewer foreigners than expected

One particularly conspicuous finding relates to overestimates regarding the number of foreigners living in Germany. Previous estimates held that there were 7.3 million people in Germany without a German passport, whereas the latest data reveal that it is instead just 6.2 million. Statisticians, again, primarily blame a failure to de-register residences in Germany once people foreigners move back home.

The new census data will carry a variety of consequences. For some German cities and states, a drop in residency numbers can have financial consequences because state subsidies are often distributed on the basis of population. Communities that must now report fewer residents may lose money.

The updated statistics could also have an effect on the shape of electoral districts, which candidates and parties will need to consider in their campaigns.

Seeking more immigration

The new numbers - particularly concerning how many people are coming and going in Germany - also raise issues for Germany's labor market.

"This means that the population is perhaps shrinking faster than we previously expected," said Herbert Brücker, a professor and researcher at the Institute for Employment Research in Nuremberg. "In particular, that has effects on the social security system."

Brücker said Germany must achieve an increase in the number of foreign workers it attracts.

"It's not just German industry that needs the increase; it's the German citizens themselves," he said. "At the end of the day, someone has to pay for pensions. And that's why we need more workers."

Even though the analysis and publication of the data from 2011 has taken two years, the census process has not yet been completed. Experts continue to pore over some of the statistics and will publish more results later. Germany's next "inventory" is slated for 2021, in accord with an EU regulation stipulating that a census must be performed once per decade.