Hi,
Just i want to create a new column from sum accumulative values begins from last record:
for example in this image it is used a OVER (PARTITION BY clause in the field CATEGORY to calculates retencion_value_3_week , but i want to keep the values from the first record to get a TOTAL accumulative value at the end or records:

I mean not to get "6" in the first record of category B in retencion_value_3_week, but "26" and after sum "15" to get not "21" but "41"
Thanks...