CREATE TABLE table_27955 ("meas. num." FLOAT, "passed" TEXT, "YES votes" FLOAT, "NO votes" FLOAT, "% YES" TEXT, "Const. Amd.?" TEXT, "type" TEXT, "description" TEXT)

What is the percentage of yes when there were 218846 yes votes
SELECT "% YES" FROM table_27955 WHERE "YES votes" = '218846'
SELECT "% YES" FROM "table_27955" WHERE "YES votes" = '218846'