1. A method comprising: identifying, by a computer-based system, a first expenditure associated with a first customer that received an ad impression; comparing, by the computer-based system, the first expenditure to a second expenditure associated with a second customer that did not receive the ad impression based on the campaign request but fits parameters associated with the campaign request; and generating, by the computer-based system, a report showing the results of the comparing, wherein a cookie is tagged with a tag based on the campaign request, wherein the cookie is installed on a web client associated with the first customer, wherein the tag includes instructions for instructing a media buyer system to bid on the ad impression for the first customer based on the tag, wherein upon navigating to a website, the cookie is transmitted from the web client to the media buyer system to indicate that the first customer is online, wherein the media buyer system purchases the ad impression that is sent to the first customer; wherein the cookie is an anonymized cookie that is stripped of PII that is associated with the first customer, wherein the first customer is part of an anonymized list of customers, and wherein the anonymized list of customers comprises cookie data associated with each customer and excludes the PII.