The end of a retailing era
In the first three months of 2009, - where it's the clothing market leader - fell by 0.3% and its profit margin shrank by 1.75 percentage points.
Which is why the pre-tax profits for 's last financial year, which ended on 28 March, are thought to have been almost 50% lower than in the previous year.
And that, believe it or not, is the good news - because some City's analysts feared it could all have been a lot worse.
Compared with the last three months of 2008, the rate of decline in M&S's sales has slowed.
The best way of seeing this is in the drop in so-called like-for-like sales (or turnover excluding the impact of new selling space) for general merchandise, which includes clothing. These plunged 8.9% in the three months to 27 December 2008 and were "only" 4.8% lower so far this year.
Time to crack open the alcohol-free, champagne-substitute, perhaps.
In clothing, which is where it really matters for M&S, Stuart Rose - the executive chairman - is confident the business has maintained its market share.
What interests me, however, is whether he thinks that we're witnessing a structural change in the economy which will have profound implications for his industry.
I spoke to him this morning and he was rather non-committal. It's what the entire industry is thinking about, he said, and was work in progress.
Hmmm.
Well here's a statistic which, I think, all consumer-facing businesses need to ponder.
In 2000, which was eight years into the longest period of unbroken economic growth in the UK since at least the nineteenth century, the ratio of UK households' debt to their disposable income was 100%.
In other words, our borrowings were roughly equivalent to all the money we have available for spending after paying taxes.
And that rate of indebtedness had been rising and was not low by modern standards.
There then followed the years of supercharged lending to financial institutions, businesses and - of course - to households.
So by 2007, the ratio of consumer debt to household disposable income had risen to 154% - and probably rose even higher through most of last year.
The availability of a mountain of cheap debt pumped up the house-price bubble and gave added oomph to a retail-spending boom of unprecedented length and intensity.
So for the big retailers, expansion was the imperative: more stores, bigger stores.
We know how that's ended - in figures like those reported today by M&S, whose only virtue is that they could have been worse.
But here's what many would see as the important point: the Bank of England and the Treasury have together taken exceptional and unsustainable steps to maintain consumer spending in the past few months, to limit the severity of the recession, by slashing interest rates, creating new money and cutting the VAT rate for a limited period.
As a direct consequence, the cash available to households for spending or saving has been massively increased (even if banks aren't passing on all the interest-rate cuts to borrowers).
Not all of this extra cash is being spent. Towards the end of last year, the British - belatedly, many would say - started saving again.
However just think what would have happened to the high street if the Bank of England and Treasury hadn't taken evasive action.
Arguably, however, the authorities have simply given a breathing space to retailers like M&S to adjust to some harsh new realities.
If a sustainable ratio of household debt to disposable income is closer to 100% than to 154%, then consumers will for an extended period save more and spend less.
That means less profit available to retailers for an indeterminate period.
The magnitude of the increment in saving may well be increased, as and when millions of households also come to terms with the collapse in the value of their pension pots caused by the global rout in stock markets of the past year.
So, for the long term, retailers almost certainly have to significantly reduce their overheads.
In the shorter term, there are two other looming icebergs.
First, there is the strong probability that taxes will have to rise after the next election, as the new government tries to put some kind of brake on the rise and rise of public-sector debt - which will squeeze households' disposable income.
Second, and to state the obvious, interest rates will rise again, as and when the Bank of England is persuaded that inflation rather than deflation is the threat.
All of which is to say that the lean years for retailing may have only just begun - and that the new winners on the high street will be reconstructing their businesses imminently.
Isn't it striking, in that context, that the UK's consistently most success retailer, Tesco, is investing heavily in creating a banking and savings business?
Other retailers, and the banks too, should probably be a little bit scared.