The message
from Terry Fields contains these words:

Not as yet. As it is fine atm I am spending very little time in the
house. If the worst comes to the worst I could always extract the
figures from the graph but they would be rather imprecise.

I can think of a way that might lend some precision, but it'll be
tedious: bring up the graph in say Paint Shop Pro, hover the cursor
over each point in turn, and use the pixel-corordinate readout to give
each point a value in X,Y format. Calibrate by doing the same for each
axis. Might get the points to a precision of 1 percent - which could
be enough for our purposes.

I don't have PSP. I do however have an old CAD package (Turbocad v6.5)
but in the past I have had problems importing objects into that.
Alternatively I could pretend it was a scanned map and take each years
co-ordinates but given the small size of the original graph | wouldn't
be at all hopeful of 99% accuracy except by sheer chance.

--
Roger Chapman