The share portfolio and its dividend income had grown tremendously over the lengthy period she had owned it. Over some forty years, at £7m it was around 65 times its value when she inherited it at a then value of £108,000 back in the thirties.
Someone with a portfolio worth £7m would be pretty rich by any ordinary standards even now - but the 1970s were quite a lot of inflation ago and so having £7m then would make one quite a lot richer still.
And there is a slight conflict in the story when it says:
Due to her blind spot with money she neither knew nor cared what shares were held and in consequence she never did any trading. The only changes to the portfolio over all those years were consequently those mandatory impositions resulting from corporate activity.
If she knew that little about her portfolio, how did those mandatory impositions resulting from corporate activity get dealt with? It seems a bit implausible that it was purely by doing nothing and letting the default actions occur: 40 years of letting the occasional cash takeover convert a holding to cash and not reinvesting the proceeds can erode a large part of a share portfolio away!
That conflict is resolvable within the story's terms - basically, if she was willing to pay "eyewateringly high fees" to a tax accountant in order not to have to do her own tax, it's entirely plausible that she would have been willing to pay a financial adviser similarly in order not to have to deal with corporate actions herself (and I'm fairly certain that if one were to make the fees eyewatering enough and give clear enough instructions, one could get the financial adviser to only take action when strictly necessary and not to bombard one with information about investments one could switch into...).
But quite possibly the real resolution lies in the introductory paragraph:
This will be my last article for 2006 and as in previous years I am presenting something a little different from the usual investment stuff. Here's a story which may be wholly fact, wholly fiction or somewhere in between.
Coupled with the fact that the story was published shortly before Christmas, the truth of the matter might just be that real life is never as simple as fairy stories!
Gengulphus