On January 15, 2016, the United Kingdom's Competition and Market Authority approved the \(£ 12.5\) billion takeover of telecommunications company EE Limited (a joint venture between the French company Orange and the German company Deutsche Telekom AG) by the United Kingdom telecommunications company BT Group plc. The regulatory authority found that the merger was not expected to result in a substantial lessening of competition within any markets in the United Kingdom. EE had reported earnings before interest, taxes, depreciation, and amortization of \(£ 1,781\) million for 2015 (EE Limited, 2016). If EE had been expected to continue to earn this amount each year in the future, what was the internal rate of return for this investment by BT?