Dominic Ng -- Chairman, President and Chief Executive Officer
Thank you, Julianna. Good morning, and thank you, everyone, for joining us for our fourth quarter 2018 earnings call. I will begin our discussion with a summary of results on slide three.
This morning we reported full year 2018 net income of $704 million or $4.81 per share, marking the ninth consecutive year that East West has achieved record earnings. Full year net income and diluted earnings per share both grew by 39% from 2017.
Our record earnings in 2018 were driven by robust year-over-year loan growth, strong net interest income growth and expanding net interest margin, controlled expense growth and stable asset quality. This was achievable because of the diligent efforts of our 3,150 associates, and I would like to thank every one of them for contributing to the success of the Company.
For the fourth quarter of 2018, we reported net earnings of $173 million or $1.18 per share, up 104% year-over-year from $85 million or $0.58 per share and up from last quarter's earnings of $171 million or $1.17 per share. Quarter-over-quarter, our net interest income grew by 6%, reaching a record $369 million in the fourth quarter and our net interest margin expanded to 3.79% for the fourth quarter. Our nonperforming assets decreased to $93 million or just 0.23% of total assets as of December 31st, 2018, and quarterly net charge-offs were 20 basis point of average loans, similar to the year-ago quarter.
Now turning to slide four. You can see that our fourth quarter return on assets was 1.69%; return of equity was 15.8%; and return on tangible equity was 18%. Our profitability ratios are consistently attractive. Our five-quarter range for operating ROA has been 1.35% to 1.84%; for ROE has been 13% to 17%; and tangible ROE has been 15.1% to 19.7%.
Looking toward 2019 and beyond, I am excited about the opportunity for East West to win new business and deepen our existing client relationships. With our presence in the United States and Greater China, we have built cross-border banking expertise that differentiates us from other banks. Despite the decline in Chinese exports and Chinese direct investment to the United States, at East West, we're actively assisting our current and prospective clients and finding opportunities for growth. Our bankers help our clients navigate the evolving geopolitical environment by providing them with expert up-to-date knowledge and understanding essential to conducting business in both markets and matching East West products and services to meet each client's unique cross-border needs.
Although some of our wholesale trade clients have scaled back their activities, on the other hand, others are taking advantage of the disruption to gain market share. Overall, our wholesale trade portfolio is up 7% year-over-year. The paths to cross-border success for East West are multifaceted, and we are comfortable that our differentiating position will serve us well in supporting the continued profitable growth of our well-diversified business.
Our outlook for 2019 is positive and we continue to invest in our business. In 2018, we invested in enhancing our cross-border team and capabilities and in upgrading our cash management platform. And in 2019, we will continue to make investments in technology to improve our fee-based income capabilities, particularly in foreign exchange and cross-border payments. And, as we have mentioned previously, another ongoing [REMOVIDO] is building a digital consumer banking platform tailored to the needs of our consumer client base.
Now moving on to a discussion on this quarter's loan and deposit growth on slide number five and slide number six. As of December 31st, 2018, total loans reached a record $32.4 billion, growing by $1.2 billion, up 15% linked quarter annualized from September 30, 2018, and growing by 11% year-over-year. In the fourth quarter, average loans of $31.5 billion grew by 13% linked quarter annualized.
Loan growth in the fourth quarter was broad-based across our lending portfolio. Our strongest quarter-over-quarter growth in average balances was in commercial and industrial loans, which were up by $427 million or 15% annualized, followed by single-family mortgage, which were up by $359 million or 26% annualized. Our CRE loans increased by $295 million or 10% annualized. Within our commercial lending this quarter, we saw strong performance in our private equity and entertainment portfolios.
On slide six you can see that total deposits grew to a record $35.4 billion as of December 31st, 2018, an increase of $1.8 billion or 21% annualized from September 30, 2018, and up by $3.2 billion or 10% year-over-year. Our fourth quarter average deposit of $35 billion also grew by 21% linked quarter annualized. By category, on an average basis, quarter-over-quarter growth was led by DDA, up by $808 million or 30% annualized, followed by money market accounts, up by $567 million or 30% annualized and certificate of deposits, up by $506 million or 24% annualized. We tend to experience seasonally strong demand deposit growth in the fourth quarter and anticipate slow growth rate in the first half of the year.
East West Bancorp Inc (EWBC) Q4 2018 Earnings Conference Call Transcript -- The Motley Fool
