U.S. stocks fell slightly on Monday after a strong week for the major averages, as investors awaited the release of major corporate earnings reports.

The S&P 500 and Nasdaq Composite slipped 0.1% each. The Dow Jones Industrial Average also shed 0.1%, or 55 points.

The moves come after both the S&P 500 and 30-stock Dow registered all-time highs on Friday, cementing a sixth straight weekly advance for both benchmarks. The S&P 500 ended the week 0.85% higher, while the Dow closed up 0.96%. The Nasdaq Composite climbed 0.8%.

Whether stocks can sustain those gains may depend on whether companies can beat expectations this earnings season, which is set to ramp up this week. Roughly one-fifth of S&P 500 companies are set to report through Friday.

Thus far, the results have been mixed. Of the 14% of S&P 500 companies that have already posted third-quarter results, 79% have beaten expectations, according to FactSet’s John Butters. However, the magnitude of those beats have been more lackluster, he noted.

The recent winning streak has investors optimistic equities still have further to run. Still, they are mindful that stretched valuations, ahead of the U.S. presidential election and amid rising geopolitical risks, could also mean further choppiness.

“If we’re not really getting the kind of confirmation that the market is worth this elevated price, you know, then we could end up seeing a digestion of gains come fairly soon,” said Sam Stovall, chief investment strategist at CFRA Research.

Elsewhere, on the economic front, leading indicators for September are due out at 10 a.m. ET.