An empty parking lot is pictured in front of a Planet Fitness gym and fitness club in Alhambra, California, on May 12, 2020, after stay-at-home orders in Los Angeles County were extended until July amid the Covid-19 pandemic. Check out the companies making headlines in midday trading. Starbucks — Shares fell 2% in midday trading following a downgrade to market perform from TD Cowen. Analyst Andrew Charles noted concern over macroeconomic headwinds in China that could hit consumer spending at Starbucks stores. Instacart — The grocery delivery stock roared out the gates as it debuted on the public market midday…