Salesforce co-CEO Marc Benioff, left, and the company's chief technology officer, Parker Harris, look on during a keynote address at Salesforce's 2013 Dreamforce conference in San Francisco on Nov. 19, 2013.

Shares of cloud software giant Salesforce dropped sharply Monday after it announced it would buy big data firm Tableau, a Seattle-based company that specializes in data visualization, for $15.3 billion in stock.

The company's stock was down as much 8% in early trading, but recovered slightly and ended the day down more than 5%.

Tableau is a leading analytics platform that will help Salesforce augment its current product offerings, which include tools to help companies with sales, marketing and customer service.

"Tableau helps people see and understand data, and Salesforce helps people engage and understand customers," Salesforce co-CEO Marc Benioff said in a statement.

The acquisition is expected to decrease fiscal 2020 non-GAAP EPS by 37 cents to 39 cents. In its last fiscal year, which ended Jan. 31, Salesforce earned $1.43 per share on $13.28 billion in revenue.

Salesforce has looked at an acquisition of Tableau for years, as indicated in this leaked 2016 document published by The Wall Street Journal.

The Tableau deal dwarfs the company's previous largest acquisition, application integration provider Mulesoft, which Salesforce bought for $6.5 billion in 2018. Other notable acquisitions include customer service platform Demandware, which it bought for $2.8 billion in 2016 and forms the basis of its Commerce Cloud product for e-commerce functions, and Heroku, an app development technology it bought for $212 million in 2010.

Correction: Salesforce bought Mulesoft in 2018. Due to an editing error, an earlier version of this article misstated the year.