WITH TBL AS (
SELECT '201303' YYMM ,'영업팀' DEPT ,23 CNT FROM DUAL UNION ALL
SELECT '201303' YYMM ,'총무팀' DEPT ,11 CNT FROM DUAL UNION ALL
SELECT '201303' YYMM ,'재무팀' DEPT ,44 CNT FROM DUAL UNION ALL
SELECT '201302' YYMM ,'영업팀' DEPT ,11 CNT FROM DUAL UNION ALL
SELECT '201302' YYMM ,'총무팀' DEPT ,21 CNT FROM DUAL UNION ALL
SELECT '201302' YYMM ,'재무팀' DEPT ,24 CNT FROM DUAL UNION ALL
SELECT '201301' YYMM ,'영업팀' DEPT ,12 CNT FROM DUAL UNION ALL
SELECT '201301' YYMM ,'총무팀' DEPT ,44 CNT FROM DUAL UNION ALL
SELECT '201301' YYMM ,'재무팀' DEPT ,33 CNT FROM DUAL
)
SELECT A.YYMM
      ,A.DEPT
      ,A.CNT
  FROM TBL A
      ,(
    SELECT DEPT
          ,ROW_NUMBER() OVER(ORDER BY CNT DESC) RSEQ
      FROM TBL
     WHERE YYMM = '201303' --조회범위의 TO YYMM
    ) B
 WHERE A.YYMM BETWEEN '201301' AND '201303' --조회범위
   AND B.DEPT(+) = A.DEPT
 ORDER BY A.YYMM DESC ,B.RSEQ   

SELECT *
  FROM t
 ORDER BY yymm DESC
     , FIRST_VALUE(cnt) OVER(PARTITION BY dept ORDER BY yymm DESC) DESC
;

두분 답변 매우 감사합니다.

진행에 많은 도움이 되었습니다.