Kevin Klotzbach
Analyst · Sandler O'Neill
Thank you, Marty. Good morning, everyone. I'll begin with a review of our financial results.
Net income was $10.6 million in the quarter. That's $2.3 million or 28% higher than the third quarter of 2017. The most significant contributors to this year-over-year increase were: net interest income was $2.4 million higher in the quarter due to organic loan growth, our provision was $700,000 lower, the effective tax rate was 19.5% as compared to 29.5% in the third quarter of 2017.
As compared to the second quarter of 2018, net income was $1.6 million lower, primarily as a result of the low loan loss provision recognized in the previous quarter. The second quarter provision was only $40,000 as compared to $2.1 million in this third quarter. Our disciplined credit culture, responsible lending practices and positive economy have all contributed to higher asset quality.
Third quarter annualized charge-offs were 28 basis points. That's 11 basis points lower than our 10-year average ending in December of 2017 of 39 basis points. The ratio of nonperforming loans to total loans was 26 basis points as of September 30, which is the lowest quarterly level we have experienced over the past 10 years. The ratio was 34 basis points as of June 30, 2018, and 48 basis points as of September 30, 2017.
Net interest margin for the quarter was 3.18%, up 1 basis point from the second quarter of 2018.
Our average loan yield increased 12 basis points, contributing to an average yield on interest-earning assets of 4.01%, which is up 13 basis points. Our cost of funds was 83 basis points, up 12 basis points from the second quarter of 2018. The increase in yield on the interest-earning assets was virtually equal to the increase in the cost of funds for the quarter. With a margin of 3.18%, 3.17% and 3.19% for the last 3 respective quarters, we believe the margin has stabilized.
We continued our efforts to convert a portion of our marketable securities in the securities portfolio into loans. Our securities portfolio decreased by $49 million in the quarter, primarily due to maturities, strategic sales and payments received on municipal bonds and mortgage-backed securities. Proceeds were used to partially fund our strong loan growth.
Over the course of the first 9 months of the year, our marketable securities portfolio decreased $123 million, with $14 million of the decline attributable to negative valuation adjustments. The remaining $109 million represents maturities, sales and payments received and then used to fund our loan growth.
Noninterest income was $1.3 million higher than the second quarter of 2018. Insurance income was up $483,000 because of the second quarter impact of nonrenewals on one of our agency specialty lines of business combined with seasonality. The first and third quarters of our insurance business continue to be higher than the income in the second and fourth quarters because of annual contingent commission revenue and the seasonality of commissions on commercial accounts. We anticipate that the seasonality will become less impactful as SDN continues to transition its book of business to a higher composition of personal life. Investment advisory income was up $334,000, driven primarily by the June 1 acquisition of HNP Capital. The net gain on derivative instruments was $276,000 higher in the quarter, as a result of interest rate swap products offerings to commercial loan customers, which was launched in the third quarter of 2017.
The increase in the gain was the result of an increase in the number and the value of transactions executed in the quarter. Income from investments in limited partnerships was up $205,000. As we have talked about in the past, this income is difficult to predict as it fluctuates based on the maturity and the performance of underlying investments. And the last significant driver of the increase of noninterest income this quarter was the net gain on the sale of loans, up $172,000 as a result of investments in our residential mortgage lending business, which has facilitated in increasing mortgage sales through the secondary market.
I'll now move on to the discussion of noninterest expenses. Expenses were above the range we have provided in last quarter's guidance, primarily driven by investments in people.
Salaries and employee benefits expense was up $1.1 million from the second quarter. As noted in the earnings press release, average full-time equivalents increased from 661 in Q2 to 681 in Q3. A few of the drivers and factors are HNP Capital, with 8 new employees, was included for the fourth quarter. We took advantage of available talent and made a few new hires earlier than anticipated, and our retail vacancies were filled.
Professional services were -- professional service expense was $457,000 higher, primarily due to legal and accounting expenses related to shelf registration filing and professional services related to the additional talent.
Advertising and promotion expense was up $228,000. You may recall last quarter, we indicated that this expense line item will fluctuate because of the timing of certain aspects of our branding campaign that was launched in February.
The effective tax rate was 19.5% in the third quarter and 19.7% in the second quarter, reflecting the lower corporate federal tax rate due to the Tax Cuts and Jobs Act.
I'd now like to provide our estimate outlook for some key areas. We anticipate low double-digit growth in our loan portfolio for the full year of 2018, with loan growth in commercial and residential lending at the higher end -- higher rate than the Consumer Indirect, mid- to high single-digit growth in nonpublic deposits for the year, a net interest margin of approximately 3.18% for the year, full year noninterest income of approximately $36.5 million, full year noninterest expense of approximately $98.5 million, an efficiency ratio for the full year of approximately 61.25%, conversion of approximately another $25 million of our securities -- marketable securities portfolio in the fourth quarter of 2018, an effective tax rate for the full year of approximately 19.5%.
And with that, I'll now turn it back to Martin.