Whether it's the sudden surge in shares of penny stocks like Opendoor Technologies Inc. or the proliferation of cryptocurrency Treasury companies, one thing is clear: Recently, investors have been drawn to shares of "story" stocks with an interesting pitch, but little in the way of actual profits.

To some, the activity in these highly speculative names seems vaguely reminiscent of the dot-com boom and bust. Then, as now, a lack of profits hasn't stopped certain stocks from tallying huge gains.

For anybody hunting for parallels between contemporary markets and 1999, BTIG's Jonathan Krinsky has a chart that might be of interest. In commentary recently shared with MarketWatch, Krinsky said that Friday marked the 60th straight trading session during which the Nasdaq-100 NDX finished above its 20-day moving average.

That is the longest streak above the short-term trend line since Feb. 5, 1999, when the Nasdaq-100 traded above it for 77 straight sessions.

After that previous streak ended in 1999, more than a year would pass before the Nasdaq and S&P 500 arrived at their dot-com bubble era peaks.

Krinsky did acknowledge that the index's gains during the 1999 runup were far larger than what investors have seen this time around. The index has gained just over 23% during this latest run, which began on April 23, FactSet data showed. By comparison, it had risen by more than 50% during the streak that ended in February 1999.

Technical analysts use moving averages as a gauge of an index of an asset's trend over a given period. The degree by which a stock or index is trading above or below a moving average can help capture the strength of its momentum.

The Nasdaq-100 includes shares of the 100 largest nonfinancial companies listed on the Nasdaq. These companies generally have a strong history of profitability. This separates stocks in the index from shares of some of the more speculative names that have boomed this year.

Still, Krinsky said the Nasdaq's latest run of success is one more sign that the U.S. stock market's recovery from the April tariff tantrum is starting to look a bit overdone.

When the Nasdaq's streak above its short-term trend line is considered alongside the explosion of interest in more speculative names - Krinsky last week pointed to the strong performance of an ETF that tracks an index of buzzy stocks widely discussed on social media as another potential warning sign - it raises questions about how closely investors are paying attention to fundamentals like the outlook for profits and sales growth, Krinsky said.

All of this could mean stocks are overdue for some turbulence, even though Krinsky doesn't think the market is close to its peak.

U.S. stocks continued to climb on Monday, with the S&P 500 SPX and Nasdaq Composite COMP on track for fresh record closing highs. This would mark a sixth straight record finish for the Nasdaq Composite, the longest such streak for the index in a year, according to Dow Jones Market Data.

The Invesco QQQ Trust Series I QQQ, an ETF that tracks the Nasdaq-100, was also poised for another record finish on Monday.