Divide previous row by next row

Hi Prath
Please consider this solution

Either by using Query Group By or DAX table functions do the following 

Create a “now” subset of your original table with just the latest value per keyword.

Create a “remainder” subset of your original table with all records except the records on the above subset.

Create a “before”  subset of your “remainder”  table with just the latest value per keyword.

You can now report “now” - “before” by keyword.