reflecting a lower store count and a slower start to the back-to-school season. On a consolidated basis, our direct-to-consumer sales represented approximately 69% of total net sales for the six months ended July 30, 2022.
Gross Profit
Gross profit increased $14.5 million, or 4.5%, to $336.8 million for the second quarter of 2022, compared to $322.3 million for the second quarter of 2021, reflecting higher net sales. As a percentage of net sales, gross profit decreased to 45.6% for the second quarter of 2022, compared to 47.7% for the second quarter of 2021, reflecting a higher mix of wholesale versus retail sales combined with higher markdowns and an increase in freight costs associated with e-commerce sales.
Gross profit increased $66.6 million, or 11.2%, to $663.8 million for the six months ended July 30, 2022, compared to $597.2 million for the six months ended July 31, 2021, reflecting higher net sales. As a percentage of net sales, gross profit decreased slightly to 45.1% for the first half of 2022, compared to 45.4% for the first half of 2021.
We classify certain warehousing, distribution, sourcing and other inventory procurement costs in selling and administrative expenses. Accordingly, our gross profit and selling and administrative expense rates, as a percentage of net sales, may not be comparable to other companies.
Selling and Administrative Expenses
Selling and administrative expenses increased $8.9 million, or 3.4%, to $268.4 million for the second quarter of 2022, compared to $259.5 million for the second quarter of 2021. The increase was driven by higher marketing expenses as a result of our strategic investment in consumer marketing to drive deeper connections with our consumers, and higher salary and benefits expenses, partially offset by lower expenses associated with our cash-based incentive compensation plans. In 2021, our first half financial results exceeded the targets established for our annual incentive plans, which resulted in a larger portion of the anticipated plan payouts recorded as expense in the second quarter of 2021. For 2022, anticipated plan payouts are being recognized more ratably during the year. As a percentage of net sales, selling and administrative expenses decreased to 36.4% for the second quarter of 2022, from 38.4% for the second quarter of 2021, reflecting leveraging of expenses on higher net sales.
Selling and administrative expenses increased $26.2 million, or 5.2%, to $529.2 million for the six months ended July 30, 2022, compared to $503.0 million for the six months ended July 31, 2021. The increase primarily reflects the factors described above. As a percentage of net sales, selling and administrative expenses decreased to 36.0% for the six months ended July 30, 2022, from 38.3% for the six months ended July 31, 2021, reflecting leveraging of expenses on higher net sales.
Restructuring and Other Special Charges, Net
We incurred restructuring and other special charges of $13.5 million ($11.9 million on an after-tax basis, or $0.31 per diluted share) during the six months ended July 31, 2021, reflecting expenses associated with the strategic realignment of the Naturalizer retail store operations. There were no corresponding charges during the six months ended July 30, 2022 or the second quarter of 2021. Refer to Note 5 to the condensed consolidated financial statements for further discussion of these charges.
Operating Earnings
Operating earnings increased $5.6 million to $68.4 million for the second quarter of 2022, compared to $62.8 million for the second quarter of 2021, primarily reflecting higher net sales and gross profit. As a percentage of net sales, operating earnings were 9.3% for the second quarter of 2022, consistent with the second quarter of 2021.
Operating earnings increased $53.9 million to $134.6 million for the six months ended July 30, 2022, compared to $80.7 million for the six months ended July 31, 2021, primarily reflecting higher net sales and gross profit. As a percentage of net sales, operating earnings were 9.1% for the six months ended July 30, 2022, compared to 6.1% for the six months ended July 31, 2021.
Interest Expense, Net
Interest expense, net decreased $9.5 million, or 78.4%, to $2.5 million for the second quarter of 2022, compared to $12.0 million for the second quarter of 2021, primarily due to the non-recurrence of the $7.1 million fair value adjustment to the Blowfish Malibu mandatory purchase obligation in the second quarter of 2021. The purchase obligation was settled for $54.6 million on November 4, 2021. In addition, we redeemed our $200 million aggregate principal of senior notes in the second half of 2021. By retiring our senior notes, we shifted our higher-rate debt to the lower-rate borrowings under our revolving credit agreement, which reduced our interest expense by approximately $3.1 million compared to the second quarter of 2021. These decreases were partially offset by an increase in interest expense attributable to higher average borrowings under our revolving credit agreement.