with t as (
select '001' col_a, '20110512' col_b, 10  col_c from dual union all
select '001', '20110511', 20 from dual union all
select '001', '20110512', 30 from dual union all
select '001', '20110511', 40 from dual union all
select '001', '20110512', 50 from dual union all
select '001', '20110511', 60 from dual union all
select '001', '20110512', 70 from dual union all
select '001', '20110511', 80 from dual union all
select '001', '20110512', 90 from dual union all
select '001', '20110511', 100 from dual union all
select '001', '20110512', 110 from dual union all
select '001', '20110511', 120 from dual union all
select '001', '20110512', 130 from dual union all
select '001', '20110511', 140 from dual union all
select '001', '20110513', 150 from dual union all
select '002', '20110513', 160 from dual union all
select '002', '20110512', 170 from dual union all
select '002', '20110511', 180 from dual union all
select '002', '20110513', 190 from dual union all
select '002', '20110512', 200 from dual union all
select '002', '20110511', 210 from dual union all
select '002', '20110513', 220 from dual union all
select '002', '20110512', 230 from dual union all
select '002', '20110511', 240 from dual union all
select '002', '20110513', 250 from dual union all
select '002', '20110512', 260 from dual union all
select '002', '20110511', 270 from dual union all
select '002', '20110513', 280 from dual union all
select '002', '20110512', 290 from dual union all
select '002', '20110511', 300 from dual
)
select col_a
     , count(case when rn5 <= 1 then col_c end) cnt_5
     , sum  (case when rn5 <= 1 then col_c end) sum_5
     , avg  (case when rn5 <= 1 then col_c end) avg_5
     , count(case when rn5 <= 2 then col_c end) cnt_10
     , sum  (case when rn5 <= 2 then col_c end) sum_10
     , avg  (case when rn5 <= 2 then col_c end) avg_10
     , count(case when rn5 <= 3 then col_c end) cnt_15
     , sum  (case when rn5 <= 3 then col_c end) sum_15
     , avg  (case when rn5 <= 3 then col_c end) avg_15
  from (
         select col_a
              , col_b
              , col_c
              , row_number()over(partition by col_a order by 1) rn
              , ceil(row_number()over(partition by col_a order by 1) / 5) rn5
           from t
     )
 group by col_a