Rolling aggregate by date


I have a table that summarizes the increase in value of a product over each yearly quarter. 

In the below example, you see the increase in value of Product 1 and 2 from 2014Q1 to 2014Q3. What I want to do is create a column that will aggregate the value of the product through time - so for example for product 1, its value changes from 1000 to 3000 to 2500 from 2014Q1 to 2014Q3. The aggregation then resets once the product ID changes.

Is there a simple way to do this in KNIME? Thankyou.

ProdID Inv_Yr Inv_Qtr Price_Incr
1 2014 1 1000
1 2014 2 2000
1 2014 3 -500
2 2014 1 2000
2 2014 2 1500
2 2014 3 -1200

You are looking for the GroupBy node. When configuring it, group by ProdID and aggregate Price_Incr using the Sum mothod. You can group additionally by year (Inv_Yr) if you want the price variations of each product within each year.