What is the total of events when the tournament was U.S. Open and the Top-25 was less than 1?
CREATE TABLE "summary" (
  "tournament" text,
  "wins" real,
  "top_10" real,
  "top_25" real,
  "events" real,
  "cuts_made" real
);
SELECT SUM("events") FROM "summary" WHERE "tournament"='u.s. open' AND "top_25"<1;