Sterling has a long history of depreciation against the US Dollar. … 1940: “The pound sterling... declining from US$4.86 to US$4.06”. (A History of the Canadian Dollar, Bank of Canada)
Early 80s brought global recession, and under Paul Volcker, “Fed policy to aggressively target the money supply rather than interest rates.” By limiting credit and thus tightening money supply the combination of this, and recession is what helped the huge spike in the value of the US Dollar. (federalreservehistory.org/Events/DetailView/44)
The pound came very close to parity at the beginning of 1985.
6. UK North Sea oil production is reported to have peaked here at ~85m barrels per month – it wouldn't have been known at the time it was the peak … The Pound rose strongly again.
7. Black Wednesday, George Soros, the ERM etc., is recent enough history. The pair made a sharp drop / corrective b wave before …
8. The discovery of the Buzzard oilfield, June 2001, the biggest in the UK, & coincides with the start of a large upward impulse C wave …
Over that period the pair remained suppressed, and just after buoyed by the transitory hope of higher interest rates in 2014, producing a relatively minor C wave.
a. given current oil price and consequent removal of incentive to do that, and b. in that North Sea oil has been pivotal to optimism for the last 40 odd years and c. in that the pair is hovering over such a critical support level at about 1.409… d. the additional pressures of Brexit, the recent BoJ move etc. etc.
… it might be time to revisit at least in sentiment, “Goodbye Sterling, it was nice knowing you.”
(I hope to get a more detailed close up time frame chart published later - there appears to be some interesting levels)