New York City saw the lowest rate of people testing positive for COVID-19 since it began keeping track of the city’s positivity rate, Mayor Bill de Blasio said Tuesday at a news conference. 

The city began tracking test positivity in March 2020, hitting a high that month of 71% of tests performed coming back as positive for COVID-19. 

Since then, the city has measured test positivity on a seven-day rolling average. It hit 0.83% as of Tuesday. 

“Since we started testing and measuring, this is the lowest level we've had,” de Blasio said. “This is a testament to the willpower of New Yorkers, fighting through this crisis, dong what we need to do to keep people safe.”

Other related metrics, such as the rate of hospitalization and the rate of new cases, have also declined steadily since January. 

Health experts have tied the improving metrics to the city’s vaccination effort. About 43.2% of the city is fully vaccinated, according to city data.