WITH t AS
(
SELECT '20150903' dt, 'A' cd, 500 cnt_i, 120 prc_i, 45 cnt_o FROM dual
UNION ALL SELECT '20150904', 'A', 100, 130, 100 FROM dual
UNION ALL SELECT '20150905', 'A',   0,   0,   0 FROM dual
UNION ALL SELECT '20150906', 'A', 300, 140, 600 FROM dual
UNION ALL SELECT '20150907', 'A',   0,   0,   0 FROM dual
UNION ALL SELECT '20150908', 'A', 150, 130,   0 FROM dual
UNION ALL SELECT '20150909', 'A',   0,   0, 130 FROM dual
UNION ALL SELECT '20150910', 'A',   0,   0,   0 FROM dual
UNION ALL SELECT '20150911', 'A',   0,   0,   0 FROM dual
UNION ALL SELECT '20150912', 'A',   0,   0,   0 FROM dual
UNION ALL SELECT '20150913', 'A', 100,  80, 150 FROM dual
UNION ALL SELECT '20150914', 'A',   0,   0,   0 FROM dual
UNION ALL SELECT '20150915', 'A',   0,   0,   0 FROM dual
)
, tmp0 AS
(
SELECT ROW_NUMBER() OVER(PARTITION BY cd ORDER BY dt) rn
     , dt, cd, cnt_i, prc_i, cnt_o
     , cnt_i * prc_i amt_i
  FROM t a
)
, tmp1( rn, dt, cd
      , cnt_s, prc_s, amt_s
      , cnt_i, prc_i, amt_i
      , cnt_o, prc_o, amt_o
      , cnt_e, prc_e, amt_e
      ) AS
(
SELECT b.rn
     , b.dt
     , b.cd
     , 0 cnt_s
     , 0 prc_s
     , 0 amt_s
     , b.cnt_i
     , b.prc_i
     , b.amt_i
     , b.cnt_o
     , ROUND((0 + b.amt_i) / (0 + b.cnt_i)) prc_o
     , b.cnt_o * ROUND((0 + b.amt_i) / (0 + b.cnt_i)) amt_o
     , 0 + b.cnt_i - b.cnt_o cnt_e
     , ROUND( (0 + b.amt_i - b.cnt_o * ROUND((0 + b.amt_i) / (0 + b.cnt_i)))
            / (0 + b.cnt_i - b.cnt_o)
            ) prc_e
     , 0 + b.amt_i - b.cnt_o * ROUND((0 + b.amt_i) / (0 + b.cnt_i)) amt_e
  FROM tmp0 b
 WHERE rn = 1
 UNION ALL
SELECT b.rn
     , b.dt
     , b.cd
     , a.cnt_e cnt_s
     , a.prc_e prc_s
     , a.amt_e amt_s
     , b.cnt_i
     , b.prc_i
     , b.amt_i
     , b.cnt_o
     , ROUND((a.amt_e + b.amt_i) / (a.cnt_e + b.cnt_i)) prc_o
     , b.cnt_o * ROUND((a.amt_e + b.amt_i) / (a.cnt_e + b.cnt_i)) amt_o
     , a.cnt_e + b.cnt_i - b.cnt_o cnt_e
     , ROUND( (a.amt_e + b.amt_i - b.cnt_o * ROUND((a.amt_e + b.amt_i) / (a.cnt_e + b.cnt_i)))
            / (a.cnt_e + b.cnt_i - b.cnt_o)
            ) prc_e
     , a.amt_e + b.amt_i - b.cnt_o * ROUND((a.amt_e + b.amt_i) / (a.cnt_e + b.cnt_i)) amt_e
  FROM tmp1 a
     , tmp0 b
 WHERE a.cd = b.cd
   AND a.rn + 1 = b.rn
)
SELECT *
  FROM tmp1
;

단가 계산식에 나눗셈이 포함되어 소수점 이하 발생하네요.
이를 보정하기 위해 반올림(ROUND) 했더니 오차가 발생하네요.
ROUND 처리를 하는게 맞는지? 빼는게 맞는지 고민해 보세요.