In Anachrony, if resources borrowed from the future through Time Rifts are not repaid by the end of the game, how severe is the penalty?

In the sci-fi time-travel board game Anachrony: in the first few eras, I borrowed a large number of Exosuits, Neutronium, and Titanium from the future through Time Rifts. If, after the asteroid impact and before the end of the game, I do not return these materials to the future through time travel, how many points is deducted for each unpaid time paradox?