Hence each network can be monitored by the users themselves. At the same time, large servers sometimes require more storage and this increases the cost since the storage has to be rented or bought exclusively for a server. However, usually peer-to-peer file sharing does not require a dedicated server. Economic impact There is still ongoing discussion about the economic impact of P2P file sharing. Norbert Michel, a policy analyst at the Heritage Foundation, said that because of "econometric and data issues, studies thus far have produced disparate estimates of file sharing's impact on album sales." In the book The Wealth of Networks, Yochai Benkler states that peer-to-peer file sharing is economically efficient and that the users pay the full transaction cost and marginal cost of such sharing even if it "throws a monkey wrench into the particular way in which our society has chosen to pay musicians and re-cording executives. This trades off efficiency for longer-term incentive effects for the recording industry. However, it is efficient within the normal meaning of the term in economics in a way that it would not have been had Jack and Jane used subsidized computers or network connections". As peer-to-peer file sharing can be used to exchange files for which the distribution right was granted (e.g. public domain, Creative Commons, Copyleft licenses, online games, updates, ...). Especially startups can save massive amounts of money compared with other means of content delivery networks. A calculation example: with peer to peer file sharing: with casual content delivery networks: Music industry The economic effect of copyright infringement through peer-to-peer file sharing on music revenue has been controversial and difficult to determine. Unofficial studies found that file sharing had a negative impact on record sales. It has proven difficult to untangle the cause and effect relationships among a number of different trends, including an increase in legal online purchases of music; illegal file-sharing; drops in the prices of CDs; and the extinction of many independent music stores with a concomitant shift to sales by big-box retailers. Also many independent artists choose a peer-to-peer file sharing method named BitTorrent Bundle for distribution. Film industry The MPAA reported that American studios lost $2.373 billion to Internet piracy in 2005, representing approximately one third of the total cost of film piracy in the United States. The MPAA's estimate was doubted by commentators since it was based on the assumption that one