NEW YORK (AP) — Stocks are off to a good start on Wall Street Monday after AstraZeneca said that late-stage trials showed that its coronavirus vaccine was up to 90% effective. The S&P 500 rose 0.9% in the early going Monday following a loss last week. Companies that would benefit the most from a reopening of the economy were among the early winners, including energy producers. Treasury yields rose in another sign of optimism. AstraZeneca became the third major drugmaker to report promising results for a potential vaccine. Unlike rival candidates, however, AstraZeneca’s doesn’t have to be stored at ultra-cold temperatures, making it easier to distribute.