Some metrics, like Earnings or Units Sold, can be added up across products. For these metrics, the Totals row displays the sum for the time period and the products that you’ve selected. For example, if you sold three resources and you earned $2 on each of those sales, the Totals row would show $6. The same logic applies to how we think about Views, Units Sold, Additional Licenses, Carts, Saved for Later, Wishlisted, and Unique Buyers.
Other metrics, however, like Conversions, Earnings per unit, Earnings per cart, Earnings per unique Buyer, and Units per unique Buyer, are percentages or ratios. Averaging those directly would give misleading results, so we calculate them from the combined totals instead. For example, Earnings per cart is calculated by taking the total number of Earnings and dividing that by the total number of Carts.