The Globe and Mail reports in its Monday edition that the list of challenges facing Canada's oil and gas sector keeps growing. The Globe's Kelly Cryderman writes that in the past 2-1/2 years, investment in Canada's energy sector has plummeted, including from foreign sources. Foreign entities accounted for 72 per cent of Canadian asset and corporate acquisitions in the oil and gas industry between 2010-14. Since then, however, this number has fallen to an average of 8 per cent a year -- including 2017 to date. A vacuum of foreign investment is especially true in the oil sands, where global energy companies have sold off $30-billion of oil sands assets this year. Royal Dutch Shell PLC, for one, says it made its decision to seek "higher returns on capital, and prioritizing businesses where we have global scale and a competitive advantage." Some energy companies looking for North American investments have shifted dollars to tight oil in the Permian basin, or other U.S. plays, where costs are lower and where the U.S. government is promising policies to transform the country into a big energy exporter. Even Canadian companies are looking to the United States to make big investments, including Enbridge and TransCanada.