Online Halloween sales are expected to increase 17% year over year, according to e-commerce platform and software provider Salesforce Inc. Commerce Cloud.

Salesforce estimates a double-digit increase in online Halloween sales in part because Halloween-related searches are already up 68% year over year, says Rick Kenney, head of consumer insights at Salesforce Commerce Cloud. Salesforce considers the Halloween shopping period as Sept. 14-Oct. 31.

“Shoppers are increasingly turning to digital; 60% begin their (shopping) hunt in a digital channel—mobile specifically,” Kenney says. “During a research-driven holiday like Halloween, where shoppers are looking to create costumes or decorations, digital is benefiting as more visits are leading to purchases.”

Salesforce also finds that 63% of Halloween searches are from mobile devices, up from 56% last year.

A recent analysis of 823 Halloween-related keywords from Sept. 1-Oct. 15 by search marketing data provider AdGooroo found that HalloweenCostumes.com accounted for 16.0% of U.S. Google text ad clicks, outpacing Amazon.com Inc., No. 1 in the Internet Retailer 2017 Top 1000, which generated 13.6%.

In addition to search, online retailers are ramping up their Halloween-related marketing campaigns.

Email marketing vendor eDataSource analyzed the email marketing campaigns between Oct. 1-11 for 16 online retailers that sell Halloween-related products including:

Spirit Halloween sent the most Halloween-related email campaigns, which eDataSource defined as having a Halloween-related word such as Halloween, costume, boo or haunted in the subject line.

Spirit Halloween sent 110 emails campaigns during this 11-day period and each campaign, on average, went to 569,000 consumers. The marketing emails had an average open rate of 10.4%. This is lower than the average open rate of 13.9% for the 16 retailers analyzed by eDataSource.

Tipsy Elves LLC’s email had the highest open rate, at 22.9%, although the retailer sent only three campaigns in this period to an average of 89,000 consumers.

Home Depot Inc., Grandin Road and Christmas Central did not send any Halloween-related email campaigns during this time period, and Target Corp. and JoAnn Fabric and Craft Stores sent one.

Of the 11 retailers that sent more than one Halloween email campaign, the median number sent was six campaigns and the average was 15.9 campaigns.