I select the entire column D and add conditional formatting.
Whenever I fill out an additional row, the cell in column D is coloured and the other ones remain white. This is the desired behaviour.
When I enter a data row underneath, Excel automatically applies the rule defined for column D to the cells in column E. A quick fix is of course to select column E and click on 'Clear Rules from Selected Cells'. But how can I avoid this unwanted behaviour from happening?