I just received my form, and they ask questions about nationality, marital status, language, ancestry, medical care situations, schooling, occupation, children, salary, transport options, size and configuration of dwellings, internet access, and more.
It is VERY comprehensive, and runs to 17 pages.
The information is all tabulated, and the forms themselves are destroyed. The raw statistics are available to government departments, businesses and others, but the individual details are not released.
The key to everything is patience. You get the chicken by hatching the egg, not smashing it.
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