Population changes in the United States and Canada.
D000293:Adolescent; D000328:Adult; D000368:Aged; D002170:Canada; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D008297:Male; D008875:Middle Aged; D011156:Population Density; D011157:Population Dynamics; D011158:Population Growth; D014481:United States