An investigation has been launched over allegations that as many as nine out of 10 frontline census officers fabricated answers - and it could mean Hong Kong's low jobless rate has been underestimated for a decade.
The Census and Statistics Department confirmed in a statement yesterday that it had "grave concerns" over reports in Ming Pao newspaper accusing frontline officers of filling in fake answers over the past 10 years.
The department said it was conducting an investigation, "with a view to getting hold of every piece of relevant information".
Its spokesman added: "Statistical work must involve professional pride when it comes to getting reliable data so as to uphold the public's trust in us as well as our reputation internationally."
Frederick Ho Wing-huen, former commissioner of the Census and Statistics Department, said an investigation was necessary.
"It would be very problematic if it affects confidence in the data," he said. "Hong Kong's reputation in this field has been good all along."
Ming Pao reported yesterday that up to half of some 180 full-time census officers had made up answers. Meanwhile, a retired census officer claimed as many as 90 per cent of the officers would make up figures.
One key area of concern was employment statistics. It was reportedly quicker and easier for officers to state that a person was not working and not looking for a job rather than unemployed but looking for a job.
Only the latter are included in the government's jobless rate, which currently stands at about 3.4 per cent.
The unnamed officer told Cable TV news: "Officers would try to finish an interview quicker by not asking some questions.
"We needed to meet some performance targets. If we were found to be too slow, it would affect our chance of promotion."
He cited as an example general household surveys in which an interview usually took more than an hour. Each frontline officer had to visit four households every day, mainly in the evening when most family members returned from work.