The CorelDRAW Graphics Suite is a perpetual license. Yours to use until upgrading your operating system makes it incompatible with your version of CorelDRAW (normally about five to eight years).
The optional annual CorelSure Upgrade Protection provides the latest version whenever it is released. (http://www.corel.com/en/volume-licensing/business/maintenance/). If you purchase and maintain CorelSure you never need to purchase the basic license again (with the exception of adding licenses!)