A number in a report is a list of people in disguise. In BrainyMetrics every count in the attribution report, on the dashboard tiles, in funnels and in custom reports is underlined: click it to see who it is.
Credit follows the selected model. Under last click one person's sale counts 1 for one campaign; under linear it may count 0.33 for each of three. So the people under a row always add up to the row's number.