Have the number of questions increased?

The questions are modified each decennial census (every 10 years) in order that:

• the needs of a substantial number of users is met, i.e. local government, central government, public services and commercial organisations;
• the questions are acceptable to the general public who complete the census forms - this is checked during field surveys;
• the highest quality data are obtained from the completed Census forms (i.e. Census form instrument is effective).

Generally, the number of questions has increased over time but occasionally there has been a decrease: the 1931 Census, for example, was less full than that held in 1921 and the 1981 census form had fewer questions than the form in 1971 (Dewdney, 1983). In fact, the first four British censuses (1801, 1811, 1821, 1831) simply asked for the number of males and females in each house and family and a question on occupation but, as time has passed, more and more information has been recorded. The 2001 Census asked 41 questions, 7 more than was asked in 1991.