If you buy Micron at the close every day and sell immediately at the open the next day, repeatedly over the long term, the returns can reach as high as 138 million percent.

But if you do the opposite:

Buy at the open every day and sell at the close, repeatedly over the long term, the final return is -99.92%.

This conclusion comes from a study by a Ph.D. in physics from MIT.

Although he has a background in physics, he has worked at top quantitative firms and has in-depth research on market data.

What's more interesting is that he didn't just study Micron; he also conducted comparative analysis on more than 20 major global stock indices.

The results show:

✅ Most market profits almost all come from "overnight gains"
✅ Buying at the close and selling at the open significantly outperforms expectations over the long term
❌ Buying at the open and selling at the close generally yields poor long-term returns

The only somewhat special case is A-shares.

In his statistics:

🇨🇳 A-shares are closer to "buy at open, sell at close" to achieve positive compound returns.

Seeing this, I suddenly understood one thing:

Why, in many impressions, the market often opens lower and then gradually rises.

No matter what news occurs, it seems to always prefer opening lower first.

And the conclusion this Ph.D. ultimately reached is even bolder:

Most of the stock market gains are not generated evenly.

Real profits are often concentrated in a few specific time periods.

As for whether this phenomenon is caused by market structure or the long-term game of vested interests, that’s left for investors to ponder.