In 2015, Acumen raised $23.7 million in philanthropic capital, an increase of 25% from the prior year. We received a $2.5M grant from the U.S. Agency for International Development (USAID) in a joint $4 million initiative aimed at generating rural economic growth in Colombia through private-sector investments-called the Investing for Peace Fund. In addition, we had non-cash revenue of $2.6 million in donated legal and consulting services, primarily to support our investing work, as well as $.4 million in donated office space. We received $0.6 million in interest income from portfolio loans, and have a loss provision of $2.3 million for portfolio investment losses, representing a conservative valuation policy. Acumen carries our program investments at cost, and we lower these valuations when impairment exists. We do not mark up our equity investments to fair market value, even when our holdings increase in value in subsequent funding rounds, in an effort to err on the conservative side. We only realize gains or profits when we exit an equity investment.
Operating Expenses & Program Investments
Operating expenses cover all the direct costs of running Acumen programs as well as our management and general and fundraising costs. They do not reflect any of our investments in our portfolio companies. Total expenses for the 2015 year were $18.7 million, which was a 20% increase compared to the prior year. These include donated services of $3.0 million. Our increases reflect growth in a number of our program areas including our Portfolio team, expanding our Leadership programs and continuing to build out our +Acumen course offering.
Program work constitutes 71% of expenses and this excludes our portfolio disbursements and the ongoing management of a growing fund. Portfolio expenses were $7.3 million, representing the cost of sourcing, due diligence, planning and the execution of $16.9 million in new investment disbursements, as well as managing our active portfolio of 67 companies. Outreach, Impact and Communications expenses were $3.9 million, representing our work in measuring our performance metrics, and the research and sharing of our insights on patient capital. Our Fellows programs have expanded in scope to $1.9 million in spend, with the Global Fellows program in its tenth year and Regional Fellows programs in East Africa, India and Pakistan. Fundraising costs and Management and General expense accounted for $5.5 million which included investments in improving organization efficiency and effectiveness.