Major U.S. equities indexes were mixed on Wednesday. The rally dating back to last week appeared to lose some momentum as Federal Reserve officials struck a cautious tone and more companies released their quarterly results.

The S&P 500 was essentially flat at the end of the midweek session. The Dow closed the day 0.4% higher, while the Nasdaq slid 0.2%.

Vistra Corp. ( VST ) became the newest component of the S&P 500 on Wednesday, and shares of the power generation company surged 9.1%, topping the benchmark index on the day of their debut. The utility reported a year-over-year revenue decline in the first quarter, reflecting an impact of storms and mild winter weather. However, Vistra expects synergies from its recently closed acquisition of nuclear-focused generator Energy Harbor to drive strong growth.

Arista Networks ( ANET ) shares jumped 6.5% following the cloud networking giant’s first-quarter earnings report. In addition to beating top- and bottom-line forecasts , Arista provided better-than-expected guidance for the current quarter amid solid demand for artificial intelligence (AI) networking solutions. The company also announced a $1.2 billion stock buyback authorization.

Shares of Globe Life ( GL ) added 5.1% after the life and supplemental health insurer declared a quarterly dividend payout. Although the firm remains the subject of a Department of Justice probe into potential fraud and a class-action lawsuit related to alleged securities law violations, Globe Life is taking steps to return value to shareholders, authorizing a stock buyback plan last week ahead of this week’s dividend announcement.

Uber Technologies ( UBER ) shares posted the heaviest losses in the S&P 500, dropping 5.7% after the ridesharing giant reported its first-quarter financial results. Although its revenue matched forecasts, gross bookings fell shy of expectations , and Uber posted an unexpected net loss as hundreds of millions in charges related to revaluations of its investments weighed on profitability.

Broadridge Financial Solutions ( BR ) shares slipped 5.4% in the wake of the fintech firm’s fiscal third-quarter earnings report. Despite improving year over year, earnings and revenue for the period came in below expectations. Broadridge now expects full-year recurring revenue growth toward the low end of its previous guidance range.

Shares of Match Group ( MTCH ) lost 5.4% after the online dating platform operator issued lower-than-expected revenue guidance for the current quarter. The subdued forecast comes as users trim their spending on dating apps in the uncertain economic environment. Worldwide downloads of Tinder reportedly fell 6% year over year in the first quarter, marking the third straight quarter of declines.