Hong Kong’s Census and Statistics Department is staffed by earnest and honest statisticians and data collectors and produces some of the most comprehensive statistics in Asia.

But the department’s just-published Summary Results of a 2011 Population Census show what looks like politically inspired manipulation of the data to hide embarrassing facts.

The huge hole in its numbers is laid even more starkly bare by the February 24 release of a study by the Asia-Pacific Foundation of Canada on Canadians in Hong Kong.

The census data purports to show separate breakdowns of the population both by Nationality and Ethnicity. Thus 93.2 percent of the population is deemed to be Chinese nationals. The largest groups of non-Chinese nationals are Indonesians and Filipinos (almost all domestic helpers on short-term contracts and limited rights) with 1.9 percent each followed by British, Indian, Pakistani, American, Australian, Nepalese, Thai and Japanese. “Other” nationalities account for 0.8 percent.

So where in this list are the Canadians? Beginning in 1987 with the realization that Hong Kong would be handed back to China in 1997, and lured by generous Canadian immigration policies, tens of thousands of Hong Kong residents migrated to the North American country. For almost a decade, Hong Kong was the biggest source of migrants to Canada. Once they attained the Canadian passports that would protect them from any harm if the Chinese government proved inhospitable, they started to trickle back. Many of these “boomerang immigrants,” as they became known, eventually returned to the territory.

Certainly all of these Canadians cannot all be included in “Other.” It is just that the Hong Kong government in practice is using an ethnic label rather than a national one as defined by passport. The Canadian survey was conducted by the Hong Kong Transition Project at Hong Kong Baptist University with a view to estimating the number of Canadians in Hong Kong and the extent of their links with and visits to Canada.

The survey concluded that “A conservative estimate of total Canadian citizens living in Hong Kong is 295,390”. It further estimates that 7.85 percent of households have at least one Canadian citizen over the age of 18.

For sure 37 percent of the number, according to the survey , they “never” considered Canada as home and only 16 percent consider it home “all the time.” But such identification issues are not supposed to enter into nationality definition. Or at any rate the data should record dual nationality if it is claimed (which technically is not possible for Chinese).

The desire to hide the actual nationality of so many Hong Kong people also distorts all the other numbers – British, American and Australian in particular. Add in ethnic Chinese who hold these and other foreign passports and the grand total of such foreign nationals is probably close to 500,000.

Then there those nationalities well represented in Hong Kong but not listed separately such as Malaysians and Singaporeans. Are ethnic Chinese from Malaysia, for example, treated as Chinese or Malaysian? If the former, the Malaysian government would have every reason to protest to Beijing.

The list by ethnicity is curious for another reason, and one which suggests that the department has scant idea about the difference between ethnicity and nationality. Indians, Pakistanis and Nepalis are all treated as separate ethnic groups as are Indonesians and Filipinos. In all cases the numbers are close to those of nationality. There are also separate categories for Thais, Japanese and Other Asians. Then there is an all encompassing category “white” which is merely an expression of skin color – and a singularly vague one at that – and could take in people from Siberia to Santiago to Saudi Arabia to Scotland.

The Department claims that ethnicity was a matter of “self-determination” in the survey. But the it chose the options which must surely have baffled many – not just the 0.4 percent of the population who opted for “other” or declared mixed ethnicity.

All in all the statistics are doubtless accurate but the definitions tell some damned lies.