CREATE TABLE table_11656578_2 (population__1980_ VARCHAR2, capital VARCHAR2)

How many people lived in the voivodenship whose capital is Siedlce in the year of 1980?
SELECT population__1980_ FROM table_11656578_2 WHERE capital = "Siedlce"
SELECT "population__1980_" FROM "table_11656578_2" WHERE "Siedlce" = "capital"