2015 was a positive year for the Plan. Our funded status improved to 91.5% as a result of contributions and investment returns. We remain on track to being fully funded by 2025.
In 2015, we produced a net investment return of 6.7% (after all expenses) for $4.8 billion in net investment income. That net return exceeded the 6.5% discount rate, which was used in 2015 to calculate the long-term cost of providing pension benefits.
In the face of low interest rates, challenging global equity markets and a significant sell-off in commodities, these are positive results. We invest globally, with assets diversified by asset class, geography, economic sector, and we also diversify across types of income streams in order to earn long-term returns. We target high-quality investments, which are resilient in times of economic stress. Strong returns from infrastructure, private equity, and real estate demonstrated the importance of diversification.