On what date was it announced that an asset was acquired for US$9 Million? 
CREATE TABLE "table1_1373542_1" (
  "asset_acquired" text,
  "acquired_from" text,
  "date_announced" text,
  "date_completed" text,
  "reported_cost" text
);
SELECT "date_announced" FROM "table1_1373542_1" WHERE "reported_cost"='US$9 million';