In 2015 ACU experienced strong deposit growth coupled with modest loan growth. As a result of the continued low interest rate environment and more modest loan growth, revenues decreased. Operating expenses also decreased, but not to the extent of revenues. Accordingly, in 2015 income was lower and the efficiency ratio was higher as compared to the prior year.
ACU ended the year with assets totaling $4.2 billion, which is an increase of $382 million or 10.1% over the prior year. The loan portfolio grew $106 million or 3.2%. Loan growth was achieved in both the consumer and commercial lending categories. Consumer lending increased $93 million or 3.4% which was driven by consumer mortgages. Commercial lending increased $13 million or 2.1% in 2015 and was driven by mortgage growth.
The deposit portfolio grew to $3.8 billion, an increase of $305 million or 8.6% over 2014. Growth was realized across all deposit products with the strongest growth being seen in savings and term deposit products which accounted for almost 80% of the growth. Growth was achieved from personal members, businesses, organizations and Outlook Financial, ACU's virtual division.
ACU generated net income of $17.2 million. ACU's profitability was impacted by a decrease in financial margin and other income of 4.8%, while operating expenses decreased 2.4%. As a result of decreased revenue and despite a reduction in operating expenses, ACU's efficiency ratio increased to 74.6%.
ACU ended 2015 with regulatory equity of $239 million which represents an increase of $16 million or 7.2% over 2014. Regulatory equity, which includes total equity and member shares, now equates to 5.7% of assets. ACU's equity measures are all in excess of the regulatory requirements. A strong equity position ensures ACU the financial strength and capacity to support growth and to make the necessary investments to meet the needs of our members and our communities.