query.sql

WITH values as (
   SELECT
     0 as value,
     '' as label,
     to_date('00000101','YYYYMMDD') as time
   UNION ALL
   SELECT
     (close - open) / close as value,
     to_char(time, 'Mon') || ' ' || to_char(time, 'YYYY') as label,
     time
   FROM "Tickers_Data"
   WHERE extract(dow from time) = $1 AND ticker = $2
 )
SELECT
  label,
  sum(value) over (order by time asc rows between unbounded preceding and current row) as cumulative
FROM values