We can't say that Charles Schwab's (SCHW +1.67%) proprietary equity index is as closely followed as, say, the S&P 500 index. But when the Schwab Trading Activity Index (STAX) rises notably, investors take notice. That was the dynamic behind the brokerage's nearly 4% price bump on Monday.
The STAX was stacked
During that day's trading session, Schwab announced that its self-named index had risen to 59.12 in June, notably up from its May level of slightly over 55. That set a multi-year high, the company pointed out.
Image source: Getty Images.
This is indicative of more than just investor eagerness to own stock, at least according to STAX's owner. The veteran financial company claims that it's a unique behavioral index "that analyzes retail investor stock positions and trading activity from Schwab's millions of client accounts to illuminate what investors were actually doing and how they were positioned in the markets each month.
The company wrote that STAX's June performance was bolstered by bargain-hunting during market pullbacks. Schwab investors were net buyers of index and exchange-traded fund (ETF) options, while they also plowed into tech, communications, and consumer discretionary stocks. By age group, the STAX data showed that Generation X investors were particularly bullish in June.

NYSE: SCHW
Key Data Points
Interesting, if non-essential
We live in a world stuffed full of securities indexes, so I wouldn't add STAX to the list of essentials to monitor. That said, it is a multi-dimensional indicator that can be revealing of investor trends and habits, factors that always affect the market to some extent.
While I wouldn't buy, sell, or hold Schwab stock based on STAX's latest performance, I'm nevertheless encouraged to see that level of activity at the brokerage.





