Online grocery sales in the U.S. are expected to exceed $100 billion for the first time in 2021, according to an eMarketer forecast. The grocery category had lagged behind many others before COVID-19. In 2020, online grocery sales surged 54% to $95.82 billion, equal to 12% of all e-commerce sales and 7.4% of grocery sales. "In 2021, this behavior will go from trial to habit for many shoppers," the eMarketer report said. Emarketer expects online grocery to reach $112.9 billion this year, en route to $187.7 billion in 2024. "With the growing number of stores offering curbside pickup and an increase in features offered by grocery delivery apps, consumers are now presented with a variety of incentives and options to order their groceries online," said Whitney Birdsall, eMarketer senior forecasting analyst. Last week, the National Retail Federation released its sales forecast for the year, with online sales expected to grow 18% and 23% to between $1.14 trillion and $1.19 trillion. The Amplify Online Retail ETF /zigman2/quotes/206522380/composite IBUY -0.49% has rallied 175.6% over the past year. The S&P 500 index /zigman2/quotes/210599714/realtime SPX +0.36% is up nearly 32%. And the Dow Jones Industrial Average /zigman2/quotes/210598065/realtime DJIA +0.48% is up 24.1% for the period.