SELECT
COUNT(*) AS 'count', 
r.`route_grade`
FROM `mc_routes` r, `mc_routeclimbs` c, `mc_areas` a, `mc_countries` co
WHERE c.`route_id` =  r.`route_id`
AND r.`area_id` = a.`area_id`
AND a.`country_id` = co.`country_id`
AND c.`user_id` = :user_id
GROUP BY r.`route_grade`
ORDER BY r.`route_grade` DESC

`route_grade` enum('3','4','5a','5a+','5b','5b+','5c','5c+','6a','6a+','6b','6b+','6c','6c+','7a','7a+','7b','7b+','7c','7c+','8a','8a+','8b','8b+','8c','8c+','9a','9a+','9b','9b+') NOT NULL,

5b   12
6c   8
7a   3

3    0
4    0
5a   0
.. etc
5b   12
5c   0
.. etc

mysql> select * from grades;
+----+-------+
| id | grade |
+----+-------+
|  1 | A     | 
|  2 | B     | 
|  3 | C     | 
|  4 | D     | 
+----+-------+
4 rows in set (0.00 sec)

mysql> select * from usergrades;
+----+-------+---------+
| id | user  | gradeid |
+----+-------+---------+
|  1 | Tom   |       1 | 
|  2 | Tom   |       2 | 
|  3 | Dick  |       3 | 
|  4 | Dick  |       1 | 
|  5 | Harry |       4 | 
|  6 | Tom   |       2 | 
|  7 | Harry |       4 | 
+----+-------+---------+
7 rows in set (0.00 sec)

mysql> select a.grade, count(gradeid) from grades a left outer join usergrades b on (a.id = b.gradeid and b.user = 'Tom') group by a.grade;
+-------+----------------+
| grade | count(gradeid) |
+-------+----------------+
| A     |              1 | 
| B     |              2 | 
| C     |              0 | 
| D     |              0 | 
+-------+----------------+
4 rows in set (0.00 sec)

mysql> select a.grade, count(gradeid) from grades a left outer join usergrades b on (a.id = b.gradeid and b.user = 'Harry') group by a.grade;
+-------+----------------+
| grade | count(gradeid) |
+-------+----------------+
| A     |              0 | 
| B     |              0 | 
| C     |              0 | 
| D     |              2 | 
+-------+----------------+
4 rows in set (0.00 sec)

mysql> select a.grade, count(gradeid) from grades a left outer join usergrades b on (a.id = b.gradeid and b.user = 'Dick') group by a.grade;
+-------+----------------+
| grade | count(gradeid) |
+-------+----------------+
| A     |              1 | 
| B     |              0 | 
| C     |              1 | 
| D     |              0 | 
+-------+----------------+
4 rows in set (0.00 sec)