Reuters adds additional reporting on the recent OPM compromise, mentioning how the data stolen from the U.S. government dates back to 1985:

The cyber attack was among the most extensive thefts of information on the federal work force, and one U.S. defense official said it was clearly aimed at gaining valuable information for intelligence purposes.

“This is deep. The data goes back to 1985,” a U.S. official said. “This means that they potentially have information about retirees, and they could know what they did after leaving government.”

Access to data from OPM’s computers, such as birth dates, Social Security numbers and bank information, could help hackers test potential passwords to other sites, including those with information about weapons systems, the official said.

“That could give them a huge advantage,” the official said.

I am extremely curious about OPM’s cyber defense architecture and how this happened.