Need a crash course on the multi row tool - Alteryx examples not help

[CDIns]

I have two rows of data, I just want to subtract one row from the other in certain columns. Can anybody walk me through the configuration of this tool? or have a good youtube video I should reference? 

Thank you, 

[alexnajm]

Tool Mastery is my favorite series: Tool Mastery | Multi-Row Formula - Alteryx Community

But here you just create a new column and do [Row-1:ColumnName]-[ColumnName] to get the difference

[CeliaC_Silje]

My experience for Multi-row Tool: 

I mostly use Update Existing Field setup to fill in null values in column (e.g., due to merged cells in Excel). 

If not sure about how the calculation is done, I use Create New Field setup to monitor the change in a new column first. 

Or just simply create a new column to refer to value in previous/ next row - understand what values are referred to first before you get into the calculation.

Below is one simple example on calculating the change in daily sales

(Anyway the Tool Mastery is always the way to go to get yourself familiar with popular use cases)

SalesChange