E-commerce threatens to upend the Top 100 Importers rankings.

Although the vast majority of the companies on the Top 100 Importer and Exporter Rankings in 2015 made repeat appearances in 2016, radical changes in the way consumers seek out and ultimately purchase goods means big changes could be in store for these rankings next year.

The changes hitting the retail sector as a result of e

-commerce are happening so quickly and so intensely that it’s possible that regular mainstays of the Top 100 Importers list could fall off the rankings, or fall apart entirely.

Retailers, which face mounting pressure from Amazon and e-commerce, hold 34 spots on the Top 100 Importers rankings and three spots on the Top 100 Exporters list.

A look at two companies – Sears and Wal-Mart – highlights the perils facing the retail industry, and possible paths to safety.

Sales at Sears stores and its Kmart brand fell 9.3 and 7.4 percent, respectively, last year, a worse performance than other retailers on the Top 100 Importers list. For example, sales at Macy’s were down 3.5 percent in 2016, and sales at J.C. Penney slid 0.6 percent. Payless Shoes is another Top 100 Importer hard hit by the

changing market, filing for Chapter 11 bankruptcy protection and closing 400 stores. Amazon, meanwhile, increased net sales 27 percent in 2016.

As traditional retailers and big-box companies struggled to adjust to the demands of online shoppers over the last several years, many have announced plans to close hundreds of stores in order to lower their costs and direct more resources to e-commerce. E-commerce sales continue to escalate, expanding 15.2 percent year-over-year in 2016, according to data from IHS Markit. At the same time, general merchandise retail sales declined 1.1 percent, and clothing and accessories retail sales fell 6.4 percent.

Last year, e-commerce accounted for 8.1 percent of US retail sales, and that figure will only rise, as IHS Markit expects e-commerce retail sales to grow more than 10 percent per year through 2022.

Wal-Mart, which is the largest US retailer and

corporation overall, has adapted better than other retailers, although it has also had to close stores as it repositions itself in the e-commerce era. Looking to shore up its competitive position against giant e-tailers such as Amazon, Wal-Mart last year paid more than $3 billion for JET.com, which was only 1-year-old at the time of the deal but already offered 12 million stock-keeping units and processed an average of 25,000 orders daily.

Target Stores also is looking to make sure the wave of e-commerce growth does not pass it by, and plans to test next-day home delivery with an initial focus on household items and dry goods.