What: The vice president of Walmart Fulfillment Services (WFS) Jaré Buckley-Cox announced that the third-party fulfillment business went through a 500% growth in gross merchandise volume last year.

Why it is important: Last year, Walmart added about 20,000 new sellers to its U.S. marketplace after only launching roughly two years ago. The expansion of the fulfillment services program has been key in "bringing more sellers to Walmart's marketplace” with a 90% retention rate for sellers joining the marketplace.

The program has been quite successful for both Walmart (which with this program is able to add to their advertising business which hit USD 2 million last year), but also the sellers themselves. The current sellers who are currently involved with the program have reportedly experienced a 50% sale growth for items. New members are also able to receive free storage and a 10% discount on fulfillment for the first 90 days for those who sign up before May of this year.

WFS is just one of a growing suite of supply chain and other services Walmart is offering to third parties. The goal for Walmart, along with creating a new revenue source from sellers, is to increase its online assortment with the prediction of reaching over 200 million items by the end of this year.

Walmart's third-party fulfillment business experienced a growth of 500% last year