origin cell "sticking" when copying and pasting across a table

Hey I'm crunching some financial ratios for a business class. I have two balance sheets side by side and I run a simple formula like "divide net sales by net income". Then I copy and paste my formula across all twelve months so I can do a full analysis.

However when I copy the formula that I have put in Cell B3 and then paste it across the row to account for each month it keeps one of the origin cells and only updates the other. So in my example when I paste it across it moves the "net profit" cell across as it should, but it keeps using the same net sales (from January) when I want it to move over to the February column.

This is what the formula looks like in B3

='IS Comparison'!B15/Table1[@[Jan.]]
Then february
='IS Comparison'!C15/Table1[@[Jan.]]

You can see that it moves from B15 to C15, but it is still dividing it by "table1@Jan" instead of bumping over to February

I thought it was doing this for every row in my ratio analysis table, but when I re did all my formulas it looks like it is only doing it for the first row of my table.

I put all my data, both my raw numbers and my final ratio analyses in tables so that I can organize it better and make it look cleaner, but if this is not compatible with copying and pasting I guess I can go back to just using ***** cells.

attached example.

thanks in advance!