How many type catagories are listed when the percentage of yes is 68.91%?
CREATE TABLE "table1_256286_61" (
  "meas_num" real,
  "passed" text,
  "yes_votes" real,
  "no_votes" real,
  "pct_yes" text,
  "const_amd" text,
  "type" text,
  "description" text
);
SELECT COUNT("type") FROM "table1_256286_61" WHERE "pct_yes"='68.91%';