Verizon once again topped the U.S. wireless industry in overall performance in the latest semiannual report from RootMetrics.

The nation's largest carrier recorded the research company's highest overall performance score for the second half of 2017 at 95 out of a possible 100 — the ninth consecutive report in which it took the top spot.

“Since launching our unlimited data plan one year ago, our network performance continues to be consistently strong,” Verizon wireless networks head Nicola Palmer said in a statement.

Among the other large domestic carriers, AT&T finished second with 92.8, followed by Sprint at 87.8 and T-Mobile at 86.8.

Verizon also swept the top spots in the other five categories tracked by RootMetrics — reliability, speed, data, call and text — although the analysis listed AT&T and Sprint as effectively tied with Verizon in the text segment.

AT&T finished second in the remaining categories. Sprint finished third in reliability and calling, although analysts noted a decline in its call performance, while T-Mobile finished third in speed and data.

Verizon also saw the most awards in the company's rankings by state and in leading metro areas.

The carrier won or shared 249 state-level performance awards in the second half of 2017, ahead of AT&T's 119, Sprint's 19 and T-Mobile's 16. Among the top 125 most populous urban areas, Verizon won or shared 601 awards over that span.

AT&T again finished second at 365 awards in metro areas, but T-Mobile gained ground in that report at 301 awards. T-Mobile CTO Neville Ray said in a statement that the company "has closed the network gap" and that its customers "are the most satisfied and are more likely to recommend us."

"They get an LTE signal more reliably and have the fastest LTE," Ray said.

Sprint trailed in the metro area analysis with 147 won or shared awards. Company officials responded in a statement that Sprint maintained its overall rankings despite being “outspent by the competition in 2017.”

RootMetrics said it conducted tests of off-the-shelf smartphones, purchased from operators' stores, while walking or driving and during both day and nighttime. The July-December 2017 analysis saw more than 4.6 million tests over some 246,000 driving miles driven and more than 8,000 indoor locations.