The ISS has spent two decades fighting drag caused by its large size and huge solar panels pushing through the tail-end of Earth's atmosphere only a few hundred kilometers above its surface.
Question: Is it possible to break down either the total delta-v or impulse delivered to the ISS over its lifetime by type of engine? If one specific individual engine unit stands out as deserving of special recognition, that would be interesting to know as well.
Presumably almost all delta-v or impulse has been imparted in orbit-raising, don't worry too much about separating any possible maneuvers of other types if they are included in the dataset and not easily separated. For that, I've just asked How often has the ISS's orbit been propulsive lowered intentionally?
note: I've used delta-v or impulse because as @Antzi points out the mass of the ISS has changed substantially over the decades and I want to avoid overly pre-constrain the answer such that an existing data base can not be used.