Ah, there's income tax returns, tax audits and then there's the long form census. And, with the long form, there's no H&R Block to help. No wonder people don't like it. It's too long, too detailed and it's not clear what all the information is used for.
Perhaps it is time for a change. A voluntary system has been proposed with a larger sampling base. The larger sampling base might compensate for the move away from a mandatory system, but it's hard to judge. The mandatory system undoubtedly contains errors as some filers emphasis speed of completion and guess work over accuracy. Presumably the voluntary system will mean those forms that are filed will at least be accurate. But who will be missed? The issue is which approach gives a better representation of the underlying population.
Another approach is to segment the form. All of the population completing a 20% segment may be more acceptable than 20% of the population completing the entire form. This approach could be coupled with a thorough review of the long form census to make sure each question contributes to some purpose. Statistics Canada should clearly explain why each data point is needed.