The graphs are drawn daily by Alexa to represent the number of hits per million users whose computers are equipped with the Alexa toolbar. The number of hits per million users determines the potential price of the site's share. The price of a share is calculated by choosing the greatest of either values: the daily price, or the 7-day average price. Thus a site with a downward graph will have its price higher than the latest number of hits (because the 7-day average will keep that price up), while a site with a rising graph will have its price at the daily number of hits.