Not sure in what context you mean "Productivity". Are you talking about "Raw Production"? If so, raw production contributes to social contruction, ship construction, research, and gross income. Manufacturing, as for instance provided by a factory, contributes only to social construction and ship construction.
On the other hand, if you're on a version of the game that predates Crusade, ignore my answer as it's been to long for me to remember how it worked back then.
