Stats Canada NHS Survey: The First Big OOPS

I spent months arguing that the changes to Canada's long form census would degrade the data from it.  Today we are starting to see proof.  Although most of the damage will come at the lower geographic levels, there appears to be evidence that some of the head-line numbers will be effected as well. From the analytic document "Immigration and Ethnocultural Diversity in Canada"

Top source countries for newcomers

 The NHS results showed that the Philippines was the leading country of birth among people who immigrated to Canada between 2006 and 2011.(3) 

However, go to footnote (3).  It reads:

(3) This result was not in line with administrative data from the Department of Citizenship and Immigration Canada which provides the number of recent immigrants by their country of birth settling in Canada each year. A number of factors could explain this difference, such as the effects of sampling, response patterns, and under or over estimation of certain groups of recent immigrants in the NHS.

So in effect Stats Canada is saying that they cannot reliably tell us which country provided Canada the largest share of immigrats during the 2006/2011 period.  A rather glaring flaw, if you ask  me.