What is 1994, when 2002 is ATP Masters Series?
CREATE TABLE "doubles_performance_timeline" (
  "tournament" text,
  "1987" text,
  "1988" text,
  "1989" text,
  "1990" text,
  "1991" text,
  "1992" text,
  "1993" text,
  "1994" text,
  "1995" text,
  "1996" text,
  "1997" text,
  "1998" text,
  "1999" text,
  "2000" text,
  "2001" text,
  "2002" text,
  "2003" text,
  "career_sr" text,
  "career_win_loss" text
);
SELECT "1994" FROM "doubles_performance_timeline" WHERE "2002"='atp masters series';