Including North Sea tax revenues, Scotland's revenue per head over the last decade has roughly matched the UK average
The green line on the graph below shows the difference in onshore (i.e. excl. North Sea) revenue generation per head; over the last decade Scotland has lagged the UK average by ~£500.
The grey shaded area illustrates the impact of North Sea revenues (allocated on a full geographic share basis) which fully explain why Scotland has at times generated higher than UK average levels of revenue per head.