SQL & PL/SQL :: Showing Monthly Data

I am having the query

SELECT JOB,
decode(to_char(hiredate,'YY'),80,to_char(hiredate,'MON'),NULL) "80",
decode(to_char(hiredate,'YY'),81,to_char(hiredate,'MON'),NULL) "81",
decode(to_char(hiredate,'YY'),82,to_char(hiredate,'MON'),NULL) "82",
decode(to_char(hiredate,'YY'),83,to_char(hiredate,'MON'),NULL) "83",
count(*) total
FROM emp
WHERE JOB='CLERK'
GROUP BY JOB,
hiredate;

I want result as follows

job 80 81 82 83 TOTAL
CLERK DEC DEC 2
CLERK JAN JAN 2

That means if 80,81,82,83 if having some common month then it should show side by side.