Under Ballmer's tenure as CEO, Microsoft's share price stagnated. The lackluster stock performance occurred despite Microsoft's financial success at that time. The company's annual revenue surged from $25 billion to $70 billion, while its net income increased 215% to $23 billion, and its gross profit of 75 cents on every dollar in sales is double that of Google or IBM. In terms of leading the company's total annual profit growth, Ballmer's tenure at Microsoft (16.4%) surpassed the performances of other well-known CEOs such as General Electric's Jack Welch (11.2%) and IBM's Louis V. Gerstner Jr. (2%). These gains came from the existing Windows and Office franchises, with Ballmer maintaining their profitability, fending off threats from competitors such as GNU/Linux and other open-source operating systems and Google Docs. Ballmer also built half a dozen new businesses, such as the data centers division and the Xbox entertainment and devices division ($8.9 billion), (which has prevented the Sony PlayStation and other gaming consoles from undermining Windows), and oversaw the acquisition of Skype. Ballmer also constructed the company's $20 billion Enterprise Business, consisting of new products and services such as Exchange, Windows Server, SQL Server, SharePoint, System Center, and Dynamics CRM, each of which initially faced an uphill battle for acceptance but have emerged as leading or dominant in each category. This diversified product mix helped to offset the company's reliance on PCs and mobile computing devices as the company entered the Post-PC era; in reporting quarterly results during April 2013, while Windows Phone 8 and Windows 8 had not managed to increase their market share above single digits, the company increased its profit 19% over the previous quarter in 2012, as the Microsoft Business Division (including Office 365) and Server and Tools division (cloud services) are each larger than the Windows division.