Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_91 (grid INTEGER, driver VARCHAR, points VARCHAR)
### Question:
What's the highest grid of Ronnie Bremer, who had more than 18 points?
### Answer:
SELECT MAX(grid) FROM table_name_91 WHERE driver = "ronnie bremer" AND points > 18