What year was Wilfred Lau separated because Capital stopped recording music?
CREATE TABLE "list_of_male_capital_artists_singers" (
  "english_name" text,
  "chinese_name" text,
  "year_signed" real,
  "year_separated" text,
  "reason_for_separation" text
);
SELECT "year_separated" FROM "list_of_male_capital_artists_singers" WHERE "reason_for_separation"='capital stopped recording music' AND "english_name"='wilfred lau';