One chart shows the astonishing growth in online grocery shopping over 9 weeks as the pandemic set in

• The pandemic has spurred a rapid adoption of online grocery shopping.
• Shoppers have historically been much slower to shift purchases online for food compared to categories like technology and apparel.

US shoppers are buying more groceries online than ever before.

Online grocery shopping in the US saw a 110% boost in daily online sales in April, according to the Adobe Digital Economic Index.

Purchases of online groceries peaked during the week of April 21, when weekly dollar sales surged as much 289% compared to the previous year, according to the analytics firm M Science.

Only a pandemic could have triggered such rapid adoption of e-commerce in the grocery category. Shoppers have historically been much slower to shift purchases online for groceries compared to categories like apparel and technology.

Walmart, the biggest seller of groceries in the US, said this week that pickup and delivery — which is primarily groceries — reached all-time high sales volumes, with sales growth surging nearly 300% at peak.

Walmart's pickup and delivery services are also attracting new customers.

"The number of new customers trying pickup and delivery has increased 4X since mid-March," McMillon said.

It remains to be seen whether customers will continue shopping online for groceries as stay-at-home orders continue to lift across the country.

McMillon seems to think they will.

"My feeling is that once this crisis is more under control, people will have seen the benefits of that service and will likely continue to use it," he told Business Insider. "It will become part of the 'new normal.'"