New data are showing strong growth in eCommerce, with Amazon.com having particularly healthy same-store sales gains.

Ecommerce grew in May to $12.3 billion, up 13 percent from a year earlier, according to ComScore Inc.

ChannelAdvisor's year-over-year same-store sales rose about 84 percent for Amazon.com and 13 percent for eBay in May, according to a Barclays Capital research note sent to clients on Friday.

Analysts at Barclays Capital said there was a strong correlation between this data from ComScore and ChannelAdvisor and the sales of Amazon.com and EBay, two of the world's largest ecommerce companies.

The secular trends in eCommerce remain strong, Anthony DiClemente, an Internet analyst at Barclays Capital, wrote in Friday's note.

Amazon.com shares climbed 1.1 percent to $185.64 in afternoon trading Friday, while EBay gained 1 percent to $28.76.

(Reporting by Alistair Barr)