112 17. COMMITMENTS The Company has various long-term operating lease agreements for the use of trans- mission facilities and premises in each of the next five years and thereafter as follows: (thousands of Canadian dollars) 2001 11,082 2002 11,212 2003 10,485 2004 9,974 2005 8,297 Thereafter 30,391 81,441 Acquisition commitments are outlined in note 3 to these consolidated financial statements. Rental expenses recognized in operating, general and administrative expenses are $3,556,000 (1999–2,470,000; 1998–$2,492,000). 18. PENSION PLANS AND POST-RETIREMENT BENEFITS The Company has a defined contribution plan for qualifying full-time employees. Under the plan, the Company contributes 5% of an employee’s earnings, not exceed- ing the limits set by the  Income Tax Act (Canada).  The Company also has defined benefit pension plans for certain employees under which the amount of the pension is determined with reference to compensation paid and length of service. The cost of benefits earned by employees is actuarially determined using the projected benefits method prorated on service and management’s best estimate of compensation increases, retirement ages of employees, future termination levels and expected returns on plan assets. The Company has a post-retirement benefits plan for certain employees which include life insurance, dental and extended health care. The benefit amount is determined with reference to the date of retirement. The current accrual method, whereby the current service cost is actuarially determined, is used in accounting for the post-retirement benefits obligation.