The Reasons Costco Thrived in 2020 From Progressive Grocer, Dec. 10: Costco Sales Continue to Climb Despite Headwinds From Progressive Grocer, Aug. 24: Costco Shares Updates on Tariffs, E-Commerce, Membership From RIS, Oct. 4: Costco Reports Q1 2010 Results FSI Report: Oct. 2, 2005
