We are a subsidiary of WEC Energy Group and were incorporated in the state of Wisconsin in 1896. We maintain our principal executive offices in Milwaukee, Wisconsin and serve customers in Wisconsin and served customers in the Upper Peninsula of Michigan through December 31, 2016. Effective January 1, 2017, we transferred our electric customers (other than Tilden, which is discussed in more detail below) and distribution assets located in the Upper Peninsula of Michigan to UMERC, a stand-alone utility owned by WEC Energy Group. See Note 21, Regulatory Environment, for more information on UMERC.
We conduct our business primarily through our utility reportable segment. Effective January 1, 2017, we transferred our investment in ATC to another subsidiary of WEC Energy Group. See Note 16, Investment in American Transmission Company, for more information.
For more information about our utility operations, including financial and geographic information, see Note 17, Segment Information, and Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations - Results of Operations.