Microsoft originally launched its subscription version of Office back in September 2012, but the company is announcing a new cheaper option for individuals today. Office 365 Personal is a $6.99-per-month (or $69.99 a year) subscription service that provides access to the Office 2013 applications for Windows, and the ability to install and use the Mac and mobile versions of the application. While the $9.99-per-month Office 365 Home Premium allows you to use the service across up to five PCs or Macs, Office 365 Personal is valid for just one computer and one tablet.

Office 365 has been slowly growing its share of subscriptions, and Microsoft revealed back in October that more than 2 million people now subscribe to the service. In the five months since, it's added an additional 1.5 million subscribers, bringing the total number of Office 365 subscribers to 3.5 million. 75 percent growth over such a short period of time is impressive, and Microsoft will be hoping that the addition of a lower price bracket will increase growth further.

Microsoft's final announcement of the day relates to Home Premium: to coincide with the launch of Office 365 Personal this spring, the company is renaming Office 365 Home Premium to "Office 365 Home."

Aaron Souppouris contributed to this article.