Here, actual numbers:
For fiscal year 2017, the NASA authorization act appropriated $19,508,000,000 to the agency. For the same fiscal year, net U.S. outlays (spending) were $4,147,000,000,000. Therefore NASA utilized 0.47% of the entire federal budget. During 1966, the height of the Apollo program, NASA was appropriated $5,933,000,000. At the time, this was 4.41% of the total federal budget. In other terms, current NASA budget is a little more than ten percent of what it was in 1966.
