In August, 1987, an enthusiastic lady wrote in with an astonishing calculation.
She had tracked the performance of all the shares chosen by Birmingham stockbrokers in The Birmingham Post share-tipping exercise the previous Christmas and discovered that the resulting "Midland Brokers' Index" had beaten every other index in sight by a mile.
Birmingham, it would seem, was awash with paper gains.
Two months later they were history. Eighteen years ago yesterday, on October 19, the stock market fell off the cliff, along with every other market in the world, except, as I recall it, Seoul and Athens. They were closed.
Our Footsie hit a 500-point loss in the first hour - 22 per cent of its then value. It recouped half the lost ground later in the day, but had given it up again within 48 hours. The " Midlands Brokers' Index" took a thrashing with the rest.
In New York the havoc was worse, prompting panicky recollections of the Great Crash of 1929 - also in October, as it happened.
Well yesterday was nothing like that. The Footsie narrowly missed clocking up its first three-digit, single-day setback for 17 months, but the damage was still less than two per cent. The 250-share, midcap index fared worse losing 185 points, but even that amounted to no more than 2.4 per cent.
Still we had a reminder that markets can be twitchy in October - it was the month of the great Asian currency crisis in 1997. This is the time of year when fund managers start to think of locking in their gains if they have had a good run - or drawing a line under their losses after a bad one.
As on October 19, 1987, a hurricane had something to do with it. This time, Wilma was churning up the Caribbean, not the Home Counties, but doing oil shares no good at all. They, along with the high-flying mining issues were suffering from a sense that this year's great commodity boom may have run its course.
By the standards of 1987, it was nobody's blood-bath. Just the same, the Footsie is now 6.1 per cent down from its recent peak of 5501.5 at the start of this month. That left it just nine points ahead of the close on July 7, the day of the terrorist attacks on London.
This month's shake-out has been largely a matter of coming to terms with the dwindling prospect of decisive interest rate cuts this winter. They dwindled further yesterday with discouraging minutes of this month's interest-setting session at the Bank of England followed by a cautious speech by Richard Lambert, supposedly one of the leading "doves" on the Bank's monetary policy committee.
Not for the first time, the mood has changed abruptly almost between one day and the next.
Three weeks ago Government over- reactions to chicken flu would have been seen as a glorious windfall for Roche, maker of Tamiflu. Instead we are getting learned discourses of the economic consequences of a global pandemic. As Rupert Neale at Montague Capital notes, this plague has killed 60 people over two years. It is not the Black Death.