Just how weak is the American consumer?

That’s what Morgan Stanley’s Mike Wilson wants to know. The short answer is that betting against the American consumer is about like betting against America in general: It often sounds good in theory — and sometimes it even looks good on paper — but it’s almost always a fool’s errand.

That was certainly the case last year. As Wilson put it in a Sunday note, “it was the consumer that buoyed growth and fended off the hard landing that many feared.”

But if you ask Mike, the mighty US spender may be weak in the knees. You just have to know where to look.

“[T]he micro data have been less resilient and are showing a more meaningful deterioration in growth, particularly in consumer services, where earnings revisions have recently broken down,” he wrote, flagging a preponderance of misses and guide-downs from “airlines, restaurants, hotels, auto and credit card companies.” “Even luxury goods companies have cited US weakness,” Wilson remarked. (No! Say it ain’t so. Or, actually, say it is so. The weaker the luxury spending impulse, the deeper my Kering discounts.)

Of course, not every consumer company’s struggling or even seeing signs of weakness. Wilson’s overarching point was just that, as he put it, “the micro data on the consumer have been weaker than the macro,” and it’s the micro data that’s forward-looking.

Speaking of forward-looking, earnings revisions breadth just turned negative. Have a look at look at the figure below, from Wilson’s short note.

The implication’s pretty clear: If you think the relationship between equity performance and revisions matters, and that it’ll “true up” (or “down,” depending on how you want to look at it), stocks may be due for additional losses atop the modest pullback seen over the past three weeks on Wall Street.

“Two weeks ago, the P/E was 22x, and it is now at 20x,” Wilson said, matter-of-factly. “If earnings revisions continue to fade, as the seasonal trends suggest they will, it’s likely these valuations have further to fall.”

For Morgan Stanley’s US equities team, the risk/reward for stocks trading at 20x “remains unfavorable,” at least at the index level.