One, probably too simple, way of looking at market rotation is that one group of stocks, for whatever reason, goes up sharply while other sectors languish. At some point, the valuation difference between the to-date winners and losers becomes so great that investors switch from the now-expensive stocks to the too-cheap.

In today’s US market, on the other hand, it has been all tech, all the time. Over the past year, for example, the IT sector is +54.5%. Ex IT, the S&P 500 is ahead by +18.1%. So far this year, IT is +20.1%. Ex IT, the S&P is +4.4%.

Micron (MU), a memory chip maker, has more than tripled since January 1. It was up by just under 20% yesterday, on news of a sharply upwardly revised brokerage house earnings estimate for this year. It’s ahead by almost 10% in the pre-market, as I’m writing this (I own shares of MU and have been scaling back recently, because the position has gotten bigger than I feel comfortable with).

On the other hand, consider Nvidia (NVDA), which is the leading light in the AI chip market. It is up so far this year, but only by about +15%. That’s better than the S&P’s +9.8%, but not by that much–and less than the IT sector as a whole.

My interpretation:

–there is rotation in the US market, but it’s either within the tech sector or from domestic tech to non-US companies

–the rotation away from NVDA is based on relative valuation and on two company-specific factors: Washington’s restrictions on exports and the loss of operating leverage as salaries shrink as a portion of operating expenses. (I’ve recently bought back some of the NVDA I sold last year (to rotate into AVGO, which I have since sold), on the idea that NVDA is now a closed-end investment company).

–the other rotation I see is from the US to the rest of the world, because even typically meh eps growth prospects there are better than we can expect from the US.