Table: albert
Columns: name
population_2011
population_2006
change
area_km
population_density

Question: What was the area in Glenella with a population of 522 in 2011?
SQL: SELECT AVG("area_km") FROM albert WHERE "name" = 'glenella' AND "population_2011" < 522

Question: What is the population density of Siglunes when the change was smaller than -8.1 percent?
SQL: SELECT COUNT("population_density") FROM albert WHERE "name" = 'siglunes' AND "change" < -8.1