Original sentence: While many active-duty USAF and other American military personnel have served, and continue to serve, as NASA astronauts, DoD still desired specially-trained military astronauts to handle classified shuttle payloads
Edited sentence: While many active-duty USAF and other American military personnel have served (about 60% of the total), and continue to serve, as NASA astronauts, DoD still desired specially-trained military astronauts to handle classified shuttle payloads