加拿大：OLD AGE SECURITY

The Old Age Security Act permits the inclusion of the OAS
program in social security agreements. These agreements
allow periods of residence and/or periods of contributions
in the other country to be counted as periods of residence
in Canada for eligibility purposes. This may help applicants
satisfy the minimum eligibility requirements for OAS
benefits. For example, someone who has resided in Canada
for less than the 10 years required to receive a partial OAS
pension in Canada would be able to use periods of residence
and/or periods of contributions in the other country to meet
the residence requirement. A similar provision would apply
for someone who has resided in Canada for less than the 20
years needed to receive an OAS pension outside the country.
Some restrictions may apply under some agreements.

Once eligibility for the OAS pension has been established,
the amount of the OAS pension payable is equal to 1/40 of
a full OAS pension for each year of actual residence in Canada
after reaching 18.


http://dsp-psd.pwgsc.gc.ca/Collection/SD18-7-2005E.pdf