Copy a formual, locking 1 data cell

You can fix your formula by using an absolute reference for F5:

Code

=(D11-(B11+$F$5)-(G11)+C11)/D11

Some explanation on references below :

Relative reference (F5)

Moves when you copy the formula.

Example: F5 → F6 → F7

Absolute reference ($F$5)

Stays fixed no matter where you copy the formula.

Use this when one value must remain constant.

Mixed reference ($F5 or F$5)

Locks only the column or only the row.

Useful when copying across rows or columns.

In your case, $F$5 keeps the value fixed while the rest of the formula updates correctly as you copy it down.