question: How many staying councillors were there when the election result was larger than 0, the new council less than 27 and the party conservatives?
answer: SELECT AVG(staying_councillors) FROM table_name_42 WHERE election_result > 0 AND party = "conservatives" AND new_council < 27
context: CREATE TABLE table_name_42 (staying_councillors INTEGER, new_council VARCHAR, election_result VARCHAR, party VARCHAR)