Only a very small number of people will ever be astronauts. In fact, for the astronaut Class of 2017, there were more than 18,300 according to NASA, and only eight to fourteen people would be accepted into the astronaut candidate program. The small number of astronauts is not likely to change for the near future. The retirement of the space shuttle and lack of a ready replacement means that there are fewer opportunities for astronauts in space. Additionally, space exploration is an expensive venture for the governments that fund it, and often the program does well to maintain current funding levels. Great increases in funding, which would allow for more astronauts, is highly unlikely. While the International Space Station has generated increased public interest and will likely continue to do so as discoveries are reported, the project still requires only a small number of astronauts at a time aboard the station.