The San Francisco Chronicle newspaper billing statements deliver advertisers' pre-printed inserts along with invoices that are mailed to newspaper subscribers throughout the month. By reaching consumers in their homes, and with the implied endorsement of an important bill, advertisers are insured a high opening rate. Only four advertisers can run in each month, so there is very little clutter. The average unduplicated circulation for this program is 250,000 every two months. Advertisers can choose to run the full unduplicated circulation or they can run the full monthly circulation (125,000) to test half of the Chronicle subscribers.