SELECT Completed_Year ,  COUNT(*) FROM building GROUP BY Completed_Year
Please show each completion year and the number of buildings completed in that year.
CREATE TABLE "building" (
"Building_ID" int,
"Region_ID" int,
"Name" text,
"Address" text,
"Number_of_Stories" int,
"Completed_Year" int,
PRIMARY KEY ("Building_ID"),
FOREIGN KEY ("Region_ID") REFERENCES "region"("Region_ID")
);
CREATE TABLE "region" (
"Region_ID" int,
"Name" text,
"Capital" text,
"Area" int,
"Population" int,
PRIMARY KEY ("Region_ID")
);
INSERT INTO  "region" VALUES (1,"Abruzzo","L'Aquila","10763","1342177");
INSERT INTO  "building" VALUES ("1",1,"La Renaissance Apartments","424 Spadina Crescent E","24","1983");