CREATE TABLE table_10837 ("Rank" FLOAT, "Constituency" TEXT, "Winning party 2007" TEXT, "Swing to gain" FLOAT, "PC's place 2007" TEXT, "Result" TEXT)

What rank was caerphilly with a Swing smaller than 6.92?
SELECT COUNT("Rank") FROM table_10837 WHERE "Swing to gain" < '6.92' AND "Constituency" = 'caerphilly'
SELECT COUNT("Rank") FROM "table_10837" WHERE "Constituency" = 'caerphilly' AND "Swing to gain" < '6.92'