CREATE TABLE table_6218 ("Election date" FLOAT, "Party leader" CLOB, "Number of votes received" CLOB, "Percentage of votes" CLOB, "Number of deputies" FLOAT)

What was deputies with the lowest number of unknown received votes, in an election year after 1986?
SELECT MIN("Number of deputies") FROM table_6218 WHERE "Number of votes received" = 'unknown' AND "Election date" > '1986'
SELECT MIN("Number of deputies") FROM "table_6218" WHERE "Election date" > '1986' AND "Number of votes received" = 'unknown'