Yahoo's core internet business is seeing huge traffic declines across the board, with its mobile users remaining mostly flat, The Information's Amir Efrati reported Wednesday, citing leaked confidential data.

Here are the most important numbers for each product as of the first week of December:

Yahoo Mail: 56.9 million total daily active users or DAUs (down 11.5% from the first week of December 2014); 24.4 million mobile DAUs (down 2.9%); and 1.2 billion total minutes per day, or 20.8 minutes per user per day (down 31.6%)

Yahoo.com homepage: 52.6 million total DAUs (down 16.5%); 11.3 million mobile DAUs (down 0.8%); 471.3 million total minutes per day, or 9 minutes per user (down 28.5%)

Yahoo Search: 43.5 million total DAUs (down 8.8%); 13.7 million mobile DAUs (down 10.3%); 606.4 million total minutes per day, or 14 minutes per user (down 18.1%)

It wasn't all bad news — Tumblr, Yahoo Weather, and Yahoo Sports all had increases in daily users.

Yahoo said during its earnings call last week that it would explore a possible sale of its core internet business, saying it would engage in "qualified strategic proposals." The company is under pressure by activist investors to make significant changes, including a sale of its core internet business, but the overall drop in active users could make it hard to find a buyer.

Verizon has been the front-runner to buy Yahoo's core business, reportedly making AOL CEO Tim Armstrong act on behalf of the company for a possible acquisition. Private-equity firms like Bain and TPG could also be interested in a potential deal, but nothing has been officially announced.

As Business Insider previously reported, Yahoo started laying off its workforce this month, including the closing of five overseas offices. Just Tuesday, it announced that it would pull the plug on Yahoo Labs, its in-house research lab.

Yahoo's spokesperson sent the following statement when we reached out: "We've made significant improvements to our core experiences and are proud of the progress we've made. Today, we attract over a billion monthly active users across mobile and desktop and are focused on continuing to improve user engagement by delivering great experiences against our seven consumer product priorities - Mail, Search, Tumblr, Sports, Finance, Lifestyle and News."

You can read the full report here>>