OMICRON
I'd hate to be disingenuous so I've replotted the data with the first trendline from 1946 to 1977 and the second using your chosen dates 1983 to 2018....
If only the track is nationalised then it is an emasculated one with limited function and improvements will be focused on existing commuter and large...
Correlation does not equal causation! That's a hugely simplified view of things and ignores things like increasing car ownership, increasing commuting...
Poll: Should the UK’s railways be renationalised?
I'd hate to be disingenuous so I've replotted the data with the first trendline from 1946 to 1977 and the second using your chosen dates 1983 to 2018....