April-June, 2008

• Dave Goodin Named CEO of MDU Resources Group’s Utility Businesses
• MDU Resources Acquires Amador Transit Mix, Inc.
• Williston Basin Interstate Pipeline announces plans to develop natural gas pipeline out of Bakken production region
  (View the Project Map)
  
• MDU Resources Declares Quarterly Dividend on Common and Preferred Stock
• MDU Resources Acquires Yarbrough’s Material & Construction
• MDU Resources Announces Director’s Intent to Sell Stock
• MDU Resources’ First Quarter 2008 Earnings from Continuing Operations Grow 72 Percent to Record Level; Company Raises Earnings Guidance
• MDU Resources to Present at the American Gas Association Financial Forum
• MDU Resources Shareholders Hear Optimistic Outlook for 2008;
  Re-elect Three Members to Board of Directors
• MDU Resources Announces Webcast of First Quarter 2008 Earnings Conference Call
• MDU Resources Reports Positive Initial Results from Bakken Wells
• MDU Resources to Present at IPAA’s Oil & Gas Investment Symposium

January-March, 2008

• MDU Resources Celebrates 60 Years on NYSE
  President and CEO Hildestad to Ring The Opening Bell(sm)
• MDU Resources to Present at Construction Materials Conference
• MDU Resources Declares Quarterly Dividend on Common Stock and Preferred Stock
• MDU Resources Announces Analyst Seminar Webcast
• MDU Resources’ 2007 Earnings Grow 37 Percent to Record Level
• Dave Goodin named president of Montana-Dakota Utilities and Great Plains Natural Gas
• Montana-Dakota Utilities Co. President and CEO Bruce Imsdahl Announces Retirement
• MDU Resources Announces Webcast of Year-End 2007 Earnings Conference Call
• MDU Resources Announces Agreement to Purchase East Texas
  Natural Gas Production Assets

October-December, 2007

• MDU Resources Initiates 2008 Earnings Guidance, Updates 2007
• MDU Resources Declares Quarterly Dividend on Common Stock and Preferred Stock
• MDU Resources Announces Webcast of Dec. 4 Conference Call
• Energy sector growth opportunities for MDU Resources
• MDU Resources Receives EEI Index Award for Outstanding Shareholder Return
• MDU Resources Announces Webcast of EEI Conference Presentation
• MDU Resources Reports Record Third Quarter Earnings; Updates Earnings Guidance
• MDU Resources Announces Webcast of Third Quarter 2007 Earnings Conference Call