Timeline 125 years of population censuses
1920
Start of mechanisation: introduction of the ‘classi-compteur’
1930
Punch card machines used to process census response
1947
Questionnaires anonymised for the first time
1960
Data processed with a ‘real’ computer , the IBM 101 Electronic
1971
Last traditional door-to-door census, public concern about privacy protection
1981
First virtual census based on the population register
1991
15 millionth inhabitant counted using population register and sample survey data
2001
16 millionth inhabitant counted in virtual census, no more need to approach people
2011
First census based almost entirely on official registers
2021
First delivery of data at grid level
2024