Puerto Vallarta, Mexico - The Mexican peso firmed marginally against the U.S. dollar in early Friday trading, buoyed by renewed optimism over Sino-American trade talks and a stronger-than-expected reading on domestic economic activity.

The spot rate opened at 19.5745 pesos per dollar, a gain of 0.03 % from Thursday’s official close of 19.5809, according to Bank of Mexico (Banxico) data. Intraday quotes have oscillated between a high of 19.6898 and a low of 19.5631, reflecting cautious mood ahead of the weekend.

Meanwhile, the U . . .