In the second quarter, Cullen/Frost earned $116.4 million or $1.80 a share compared with earnings of $93.1 million or $1.47 a share reported in the same quarter last year and compared with $113.9 million or $1.77 a share in the first quarter.
Overall, average loans in the second quarter were $17.2 billion, a decrease of 1.7% compared to $17.5 billion in the second quarter of last year.
Excluding PPP loans, second quarter average loans of $14.6 billion represented a decline of 3% compared to second quarter of 2020.
Average deposits in the second quarter were $38.3 billion, an increase of more than 22% compared with $31.3 billion in the second quarter of last year.
Our return on average assets and average common equity in the second quarter were 1.02% and 11.18%, respectively.
Net charge-offs for the second quarter totaled $11.6 million compared with $1.9 million in the first quarter.
Nonaccrual loans were $57.3 million at the end of the second quarter, a slight increase from $51 million at the end of the first quarter and primarily represented the addition of three smaller energy loans, which had previously been identified as problems.
A year ago, nonaccrual loans stood at $79.5 million.
Overall delinquencies for accruing loans at the end of the second quarter were $97.3 million or 59 basis points of period-end loans and were at manageable pre-pandemic levels.
We've discussed in the past $2.2 billion in 90-day deferrals granted to borrowers earlier in the pandemic.
Total problem loans, which we define as risk grade 10 and higher were $666 million at the end of the second quarter compared with $774 million at the end of the first quarter.
I'll point out that energy loans declined as a percentage of our portfolio, falling to 6.98% of our non-PPP portfolio at the end of the second quarter as we continue to make progress toward a mid-single-digit concentration level of this portfolio over time.
Those of these portfolio segments, the total, excluding PPP loans, represented $675.1 billion at the end of the second quarter, and our loan loss reserve for these segments was 8.6%.
Through the midpoint of this year, we added 7% more new commercial relationships than we did in 2020, which included the outsized second quarter of 2020 when PPP activity was so strong.
Looking at recent trends, our new commercial relationships were 511 in the fourth quarter of 2020, 554 in the first quarter of this year and 643 in our most recent quarter.
Were up about 6% in both of those in terms of new customers.
And also, as many others, we're seeing good growth in wealth management from assets under management with these good markets, but have also seen an increase of around 3% in new customers.
In the time since we began our PPP efforts, just under 1,000 new commercial relationships identified our assistance in the PPP process as a significant reason for moving to Frost.
New loan commitments booked during the second quarter, excluding PPP loans, were up by 9% compared to the second quarter last year and up by 45% on a linked quarter basis.
Our current weighted pipeline is 12% higher than one year ago, 17% higher than last quarter and 38% higher than the same time in 2019.
In total, the percentage of deals lost to structure of 56% was down from the 75% we saw this time last year, but that's really more a factor of the increase in price competition rather than more market discipline around structure.
We were extremely proud to have completed our 25 branch Houston expansion initiative in the second quarter, and we continue to be very pleased with the results.
Our numbers of new households were 141% of target and represents almost 11,000 new individuals and businesses.
Our loan volumes were 215% of target and represented $300 million -- $310 million in outstandings and about 80% represented commercial credits with about 20% consumer.
Regarding deposits, at $433 million, they represent 116% of target, and they represent about 2/3 commercial and 1/3 consumer.
This represents about 13,500 net new checking customers.
Our previous high was 12,700 for full year 2019 and it's all organic growth.
Houston accounts for about 1/3 of this relationship growth.
Their annual growth rate for consumer customers is up over 13%.
That compares to 4% in 2018 before we started the expansion.
This makes a difference in the lives of people who live paycheck to paycheck, and that was on top of our $100 overdraft grace feature that we rolled out in April.
Also, earlier this month, we reached an ATM branding partnership with Cardtronics that will result in us having more than 1,725 ATMs in our network across Texas.
I mentioned PPP earlier and how our efforts helped thousands of small businesses, and we closed out the second round of PPP with more than 13,000 loans for $1.4 billion.
And combined with the first round, that gives us a PPP program total of more than 32,000 loans and $4.7 billion in deposits -- $4.7 billion in outstandings.
We've already submitted 21,000 forgiveness applications and received approval on nearly 19,100 of them for $3 billion.
Our net interest margin percentage for the second quarter was 2.65%, down seven basis points from the 2.72% reported last quarter.
Interest-bearing deposits at the Fed averaged $13.3 billion or 31% of our earning assets in the second quarter, up from $9.9 billion or 25% of earning assets in the prior quarter.
Excluding the impact of PPP loans, our net interest margin percentage would have been 2.37% in the second quarter, down from an adjusted 2.59% for the first quarter with all of the decrease resulting from the higher level of balances at the Fed in the second quarter.
The taxable equivalent loan yield for the second quarter was 4.28%, up 41 basis points from the previous quarter and was impacted by an acceleration of PPP forgiveness during the quarter which accelerated the recognition of the associated deferred fees.
Excluding the impact of PPP loans, the taxable equivalent loan yield would have been 3.80%, up three basis points from the prior quarter.
To add some additional color on our PPP loans, forgiveness payments received accelerated during the quarter, totaling $1.3 billion compared to the $580 million received in the prior quarter.
As a result of the accelerated forgiveness, interest income, including fees on PPP loans totaled about $45 million in the second quarter, up significantly from the approximately $30 million recorded in the first quarter.
Given our current projections on the speed of forgiveness of the remainder of our PPP loans, we currently expect that the interest income on PPP loans recognized in the third quarter would be less than 1/2 of the $45 million recorded in the second quarter.
Total forgiveness payments through the second quarter were approximately $2.7 billion.
And total PPP loans at the end of June were $1.9 billion, down from the $3.1 billion at the end of March.
At the end of the second quarter, we had approximately $38 million in net deferred fees remaining to be recognized, and we currently expect a little over 70% of that to be recognized this year.
The total investment portfolio averaged $12.3 billion during the second quarter, up about $46 million from the first quarter.
The taxable equivalent yield on the investment portfolio was 3.36% in the second quarter, down five basis points from the first quarter.
The yield on the taxable portfolio, which averaged $4.2 billion was 2.01%, down five basis points from the first quarter as a result of higher premium amortization associated with our agency MBS securities, given faster prepayments.
Our municipal portfolio averaged about $8.1 billion during the second quarter, down $104 million from the first quarter, with a taxable equivalent yield of 4.09%, flat with the prior quarter.
At the end of the second quarter, 78% of the municipal portfolio was pre-refunded or PSF-insured.
The duration of the investment portfolio at the end of the second quarter was 4.4 years, in line with the first quarter.
Investment purchases during the quarter were approximately $680 million and consisted of about $400 million in municipal securities with a TE yield of about 2.30% and about $190 million in 20-year treasuries with the remainder in MBS securities.
Regarding noninterest expense, looking at the full year 2021, we currently expect an annual expense growth rate of around 3% from our 2020 total reported noninterest expenses.
And regarding income tax expense, the effective tax rate for the quarter was 11.3%, up from the 6.4% reported in the first quarter as a result of higher earnings, but also impacted by lower tax benefits realized from employee stock option activity in the second quarter as compared to the first.
We currently are projecting a full year 2021 effective tax rate in the range of 9% to 9.5%.
Given our second quarter results and recognition of lower PPP fee accretion for the remainder of the year, we currently believe the current mean of analyst estimates of $6.33 is reasonable.

Summary:
In the second quarter, Cullen/Frost earned $116.4 million or $1.80 a share compared with earnings of $93.1 million or $1.47 a share reported in the same quarter last year and compared with $113.9 million or $1.77 a share in the first quarter.