This article shows that although Shutterstock has increased its portfolio by over 300% over the last 3 years, it has only increased downloads by around 9%.
http://www.selling-stock.com/ViewArticle.aspx?id=84743e14-8f7e-49e0-8e64-0deff8dcd563
FYI, you do have to pay to view the article.
http://www.selling-stock.com/ViewArticle.aspx?id=84743e14-8f7e-49e0-8e64-0deff8dcd563
FYI, you do have to pay to view the article.


