The average number of times per month that the full text of each article from The EMBO Journal, published from July-December 1999, was accessed.
After an initial peak during the month immediately following publication, the usage declines to a steady level of about 6% of the initial figure and continues at about this level thereafter. Once free access is introduced, 12 months after publication in this case, usage continues at about the same rate as when access was restricted to those who had paid for it. Over a 2-year period, about 40% of usage occurs after the first 6 months of publication.