I don't know what the source is but it doesn't seem that good. For example - the cost of the F-35 program is insane. It's at $2 trillion right now but that's only the current estimate. The project cost is certain to keep going up and it might be $2.5+t or who-knows-what in a decade.
The F-35 fighter will now cost more than $2 trillion | Responsible Statecraft