How to use =B3-B2 in airtable

[Odiez]

Good day

I am new to airtable.

I want to know on how to do something like =B3-B2 and show in C3 in iartable but for full column

I did try 

{Notes} - {Notes}

in my column Notes row 1 is 111 and row 2 is 97

But is shows 0 instead off 14 in my next column

[TheTimeSavingCo]

To do this you're going to need to utilize linked records

You'll need to:
1. Create a linked field to the same table
2. In row 3, add a link to row 2
3. Create a lookup field to display the "Notes" value from row 2
4. Create a formula field to deduct the values accordingly