Matthew Funke
Analyst · Piper Sandler
Sure. Thanks, Greg.
Well, in the December quarter, we earned $1.32 diluted. December is the second quarter of our fiscal year. And that's an increase from $0.23 diluted in the September quarter, and it's up $0.48 from the same quarter a year ago when we earned $0.84. Sequentially, net interest income increased due mostly to acceleration of deferred fee accretion on PPP loans as those balances were forgiven. Noninterest income increased due mostly to nonrecurring factors, provision for loan losses declined modestly and noninterest expense was little changed.
Compared to a year ago, noninterest income was up a little more than $2 million as gains on residential loan sales were $1.2 million higher and that nonrecurring, bank-owned, life insurance benefit added almost $700,000. In the -- as compared to the linked quarter, that BOLI item accounted for most of the noninterest income increase of almost $800,000, while an increase in secondary market gains was mostly offset by the inclusion in the linked quarter of a nonrecurring wealth management benefit.
Year-over-year, excluding the onetime item, we saw higher interchange income and servicing income, partially offset by lower-deposit service charges. In mortgage, our volume originations was more than 4 times the year ago period, and the average gain per loan remains slightly higher as well. We're also generating more in mortgage servicing income as the dollars under servicing continued to increase sharply, and we generated new mortgage servicing rights with our increase in originations. Compared to a year ago, our loans under servicing were up by about $80 million, which is a 50% increase.
Debit card interchange and deposit service charges continue to follow similar trends from recent quarters. And as a percentage of average assets, our noninterest income annualized was 89 basis points, of which 11 basis points was attributed to the BOLI benefit. In the same quarter a year ago, we were at 65 basis points annualized with nothing identified as nonrecurring. And in the linked quarter, we showed 78 basis points, of which 3 basis points was the nonrecurring book management item.
Noninterest expense was up 3.1% compared to the same quarter a year ago and down 0.5% as compared to the linked quarter. A year ago, we had a $350,000 nonrecurring items total mostly due to loss on a fixed asset disposal. And in the linked quarter, we had $150,000 in nonrecurring compensation expense related to wealth management.
We also recorded a charge for provision for off-balance sheet credit exposure at $388,000 in the current quarter, up from $362,000 in the same quarter a year ago and as compared to a charge of $226,000 in the linked quarter. Compared to the year ago December quarter, significant changes on what we see as a core basis are compensation and occupancy up 8% and 5%, respectively; data processing, up 34%; deposit insurance, up to $218,000 in the current quarter from 0 in the same quarter a year ago; and advertising remains below trend and core deposit and tangible amortization is lower by about $100,000 per quarter as a couple of CDIs from some older acquisitions have rolled off.
As a percent of average assets, noninterest expense is down about 20 basis points compared to the same quarter a year ago. Excluding fixed asset losses in that year ago period, we'd be down about 11 basis points and most of that decrease would be attributable to our higher-average assets resulting from the PPP loans.
Our net interest margin in the December quarter was 3.92%, which included about 8 basis points of contribution from fair value discount accretion on acquired loan portfolios and premium amortization on assumed deposits, which were about $478,000 in dollar terms. Also, the accelerated origination fee accretion on the PPP loans, as those were forgiven, added another $968,000 to interest income, which contributed 16 basis points to the margin.
A year ago in December, our margin was 3.70%, of which 10 basis points resulted from fair value discount accretion. And we also had some benefits in that quarter from loans that had previously been on nonaccrual and returned to accrual status or resolved otherwise, those added another 4 basis points to the reported margin. So on what we see as a core basis, our margin is up about 11 basis points from December 2019 to December 2020. We see our core asset yields down 55 basis points, core cost of deposits down 66% and total core cost of funds down 68%.
Making that same comparison to the September quarter when we had a reported margin of 3.73%, we had less discount accretion, which had added 6 basis points of benefit to that margin, and we didn't have any impact from PPP forgiveness. So on a core sequential basis, we saw less than 1 basis point decline.
Greg noted nonperforming loans and assets were stable in the current quarter at about $11 million. Nonperforming assets are down about $3 million from the same quarter a year ago. That's due primarily to a reduction in problem loans and assets from the Gideon acquisition from November 2018.
At $224,000, net charge offs were a bit higher in the December quarter as compared to the linked September quarter, and they're 4 basis points annualized on average loans. That's the same as our trailing 12-month figure. We've had about $800,000 in net charge offs over the last 12 months. A year ago, that trailing 12-month figure was 3 basis points on average loans. With limited loan growth, stable credit metrics in our outlook and the required provisioning remains limited, we set aside just over $600,000, which is 11 basis points annualized. Looking back over the last 12 months, provisioning has totaled $6.1 million or 29 basis points on average loans over that period.
The effective tax rate was 20.7%, down a bit from the linked quarter and up a bit from the year ago quarter. Over the last 12 months, our effective tax rate has also been 20.7%. And we're trending higher from 19.8% on a trailing 12-month basis a year ago.
Looking at the balance sheet. Gross loan balances were down in the December quarter as PPP forgiveness more than offset growth elsewhere. Gross balance is down about $29 million, while PPP balances declined $38 million. Compared to 12 months ago, gross loan balances are up $162 million outside of the Central Federal acquisition and up about $66 million outside of both the acquisition and PPP loans, which would translate to about a 3.4% core growth rate. Last year at this time, without any noncore growth to adjust for, we were running about 6.8% on a 12-month basis.
The investment portfolio is up modestly, and we continue to see cash flow from our mortgage-backed securities, some municipal calls. We're picking up more in cash balances in total than we want to, but we're being cautious about locking in asset yields also. Total assets were up $82 million in the December quarter, with cash up more than $100 million.
The allowance as a percentage of our gross loans increased to 1.64% at December 31, up significantly since June 30, primarily due to the adoption of the CECL standard while provisioning in excess of net charge offs has also added another $1 million. The allowance would have been 1.72% as a percentage of gross loans outside of PPP, up 1 basis point from the linked quarter.
Deposits were up $97 million in the December quarter following a decline in the September quarter, which was the only quarter of the calendar year where we didn't post strong deposit growth. Brokered funding was down $5 million in the current quarter, while public unit deposits were up $32 million, more than reversing the decrease we had seen in the September quarter in public units.
Time deposits outside brokered funding were down by $25 million this quarter, similar to what we saw in the September quarter and almost 9% lower than our balances 1 year ago outside of the Central Federal acquisition. We've seen strong growth in CDs through mid-2019, while rates were headed higher.
Nonmaturity deposits were up $122 million in this most recent quarter, and they're up 29% as compared to 12 months ago outside of the Central Federal acquisition. Nonmaturity growth had slowed in late 2018 into early 2019 as depositors had shown a preference for time deposits, and now that is in full reversal.
FHLB advances are down $22 million in the December quarter as we don't really have a need for the funding. Compared to December 31 a year ago, advances are down about $51 million.
Greg, I'll hand it back over to you for some strategic comments.