Tracked means "followed" and I find the meaning clear enough, but if you don't then please substitute "kept pace with" and/or rewrite as needed to clarify the point, which is the productivity - wage gap.
I'm not sure what industry you're in but professionally when we talk about one instrument's relationship to an underlying asset we describe it as tracking or following it, even if that tracking/following is some function of the underlying rather than a direct linear relationship, rarely in life is anything directly proportional.
"Kept pace with" is fine, consider using this in future.
2. Wages have not tracked productivity increases for half a century or more.
3. Over the past 40+ years, automation appears to have increased income disparity.