On the example above there are two low performing bidders - SSP 5 & SSP 8. They generate 2% and 1.6% of total revenue respectively. When we consider only total revenue, it seems correct to remove SSP 8 as it contributes less to the bottom line. However, only 43% of SSP 5's revenue is incremental, which means we would lose approx. 0.8% of total revenue if remove SSP 5 from the header. In turn, SSP 8 generates 56% of incremental revenue, 0.9% of total revenue on the site. As a result, it makes more sense to remove SSP 5 than SSP 8.