INSERT INTO ForgeRock
    ([productName], [description],grade)
VALUES
    ('OpenIDM', 'Platform for building enterprise provisioning solutions',10),
    ('OpenAM', 'Full-featured access management',20),
    ('OpenDJ', 'Robust LDAP server for Java',30),
    ('OpenDJ', 'Robust LDAP server for Java',40),
    ('OpenDJ', 'Robust LDAP server for Java',50),
    ('OpenDJ', 'Robust LDAP server for Java',60),
    ('OpenDJ', 'Robust LDAP server for Java',70);

1                   90-100

3                   80-90

2                   70-80

.
.
.

3                   10-20

3                   0-10

SELECT * FROM
(SELECT
    count(productName) studenttotal,grade
  FROM ForgeRock
  WHERE grade >= 90
  GROUP BY grade
UNION ALL
SELECT
    count(productName) studenttotal,grade
  FROM ForgeRock
  WHERE grade < 90 AND grade >= 80
  GROUP BY grade
UNION ALL
SELECT
    count(productName) studenttotal,grade
  FROM ForgeRock
  WHERE grade < 80 AND grade >= 70
  GROUP BY grade) a
ORDER BY grade;