@richardknott this was expected. Several industry analyses had predicted a decline in PHEV as BEV adoption extends penetration. I think the #BNEF people did a chart, or maybe it was the #emberenergyreport.
Headline is somewhat confusing because the decline is PHEV only. The Chinese term “NEV” includes both PHEV and BEV. The dip will be structural now, not cyclical so unlikely to be rare, but rather the first in a series of increasingly steep declines.