Backfills occur when a visitor skips at least one step between the step at which the visitor entered and the step at which the visitor exited the funnel. For example when you have a funnel with four steps, and a visitor converts the funnel directly from step 2 (skipping step 3), then you see an entrance to step 2, a backfilled hit for step 3 and a hit for the funnel conversion.

To see the actual number of hits hover the number of shown step hits below the step name. The segmented visitor log shows only the visitors that actually navigated through this step.

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