Locally, though, it can be clearer. Over the past seven days, San Francisco, home to more than 870,000 people, recorded an average of only 26 new Covid-19 cases per day. Two-thirds of all adults in San Francisco and almost 60 percent of the greater metro area of 4.7 million have been vaccinated with at least one dose — one of the highest rates in the U.S. Its positive test rate sits at 1.2 percent. Throughout San Francisco, there are signs of residents beginning to relax their emergency precautions, at least slightly, and enjoy a reward from vaccinations. Some people are going maskless during walks outdoors — a rare sight until recently — while small gatherings like running and cycling clubs have resumed and in-studio yoga and other fitness classes have restarted. Prompting a burst of municipal applause, the main branch of the city's library reopened Monday for browsing, and the city could enter California's "yellow tier" — the least-restrictive pandemic tier — this week. And there are signs that the city is preparing for a long-term reopening. Kevin Carroll, executive director of the Hotel Council of San Francisco, a trade group for the city’s hotel industry, said a majority of San Francisco’s 34,000 hotel rooms are expected to be open by the end of May. More downtown offices, including those of major tech companies, are in the process of coming back. Salesforce, the software company that occupies San Francisco’s tallest skyscraper, is targeting a reopening of its headquarters this month, spokesperson Annie Vincent said.