About 100 "Public Affairs Bulletins" were generated before congressional appropriators ended their production in 1951. Senate appropriators have advised NASA to plan for a launch no later than 2020. In addition, all appropriative rights are subordinate to riparians or earlier appropriators. The act however, was extended by appropriators each fiscal year until the early 1960s. Appropriators have not funded the program since FY1998. The resource units withdrawn from the system are typically owned individually by the appropriators. The new generation of appropriators considers themselves "archeolog[es] of the present time".