At the beginning of the 1970's, the UK was exporting 36% more passenger cars than it was importing. To put that into time context, the UK joined the EU in 1973. By 1977 it was neutral and thereafter it has been in the minus region.
In 1970, BLMC was in a net positive of 354,000, Chrysler (Hillman) 147,000, Ford 126,000, Vauxhall 61,000 and Jaguar 16,000. Land Rover's passenger car sales were negligible at this time. Taking off imports the net positive was 456,000.
By 1978, BL was almost alone, with 212,000 more export cars, Chrysler 83,000, JLR 23,000. Vauxhall was now minus 47,000 and Ford -68,000. In total the UK was now a net importer to the tune of 369,000 cars. That's a turn around from 1971 of minus 825,000 cars! Just eight years. Staggering.
Ford and GM were moving production to the EU and BL was in trouble so a double whammy. Just when it looked all over, the cavalry arrived in the form of Japanese car makers. Nissan in 1988, Honda 1992 and Toyota 1993. It wasn't enough to return to positive territory but it stopped the rot.
Then Peugeot (who had taken over from Chrysler) pulled out of the UK around the same time BMW left MG Rover in a mess which folded shortly after. Toyota allowed its operation in the UK to shrink, Carlos Ghosn's departure from his post coincided with Nissan's UK diminished role within the R-N alliance and Honda left European manufacturing.
In 2022 the UK imported more than double the cars than it exported. Then a couple of the remaining players are seeking more government inducements to keep on investing in UK car manufacturing. One rather cynically as it recently posted huge global profits. I guess when some sense vulnerability...
The UK public has long since stopped caring for its car industry. Some say foreign ownership means zero benefit for the economy. Either a feeble attempt to justify their lack of support or maybe they need to give their heads a wobble.
I'm picking it may retreat back under the 50% mark in 2023 but not by much if it does. Will the locals care if the UK car manufacturing lives or dies? I'll let Joni Mitchell have the last say: "Don't it always seem to go. That you don't know what you've got 'til it's gone?"