What is the highest placing for  marie mcneil / robert mccall, with less than 168.58?
CREATE TABLE "ice_dancing" (
  "rank" real,
  "name" text,
  "nation" text,
  "points" real,
  "placings" real
);
SELECT MAX("placings") FROM "ice_dancing" WHERE "name"='marie mcneil / robert mccall' AND "points"<168.58;