Our performance for the first six months of 2021 is due to the tremendous effort of our talented 11,000-plus teammates that deliver creative risk management solutions for our customers.
We delivered $727 million of revenue, growing 21.5% in total and 14.7% organically.
Our EBITDAC margin was 32.9%, which is up 340 basis points from the second quarter of 2020.
Our net income per share for the second quarter was $0.49, increasing 44% on an as-reported and adjusted basis, with the latter excluding the change in estimated acquisition earn-out payables.
However, not all companies are back at 100%, and we continue to hear about struggles with certain customer segments in hiring workers.
Admitted rates continue to be up 3% to 7% across most lines.
the outliers are workers' compensation rates which remain down 1% to 3% and commercial auto rates which were up 5% to 10%.
From an E&S perspective, most rates are up 10% to 20%.
Coastal property, both wind and quake, are up 15% to 25%.
Professional liability rates are generally up 10% to 25%-plus, cyber rates are generally up 10% to 20%-plus, with increased underwriting questions and some reduction in coverage availability.
From an M&A perspective, we closed two transactions during the quarter with the annual revenues of, approximately, $11 million.
Retail delivered an outstanding organic growth of 17.6% for the second quarter.
National Programs grew 13.3% organically, delivering another great quarter.
The Wholesale Brokerage segment delivered a solid quarter with 12.3% organic growth.
The Services segment had a good quarter and delivered organic revenue growth of 4.6%, primarily driven by claims processing revenue.
For the second quarter, we delivered total revenue growth of $128.5 million or 21.5% and organic revenue growth of 14.7%.
EBITDAC increased by 35.4%, which expanded EBITDAC margin by 340 basis points, despite lower margin associated with certain acquisitions completed in the past few quarters and slightly higher travel costs.
Income before income taxes increased by 44%, growing faster than EBITDAC due to a lower growth rate in amortization and interest expense, as well as a decrease in acquisition earn-out payables.
Net income increased by $42.5 million or 43.9% and our diluted net income per share increased by 44.1% to $0.49.
The effective tax rate for the second quarter of this year and last year was 25.2%.
We continue to anticipate our full-year effective tax rate for 2021 will be in the 23% to 24% range.
Our weighted average number of shares increased slightly compared to the prior year and our dividends per share increased to $0.093 or 9.4% compared to the second quarter of 2020.
For the second quarter of this year and last year, the impact was minimal with the adjusted and as-reported diluted net income per share of $0.49 growing 44.1% over the prior year.
For the quarter, our total commissions and fees increased by 21.3% and our contingent commissions and GSCs increased by 2.2%.
Organic revenue, which excludes the net impact of M&A activity and changes in foreign exchange rates, increased by 14.7%.
The Retail segment delivered total revenue growth of 28.3%, driven by acquisition activity over the past 12 months and organic revenue growth of 17.6%, which was driven by growth across all lines of business.
Organic growth for the quarter was positively impacted by, approximately, 300 basis points due to the $8 million adjustment recorded in the second quarter of last year for the economic disruption associated with the pandemic.
EBITDAC margin for the quarter increased by 510 basis points and EBITDAC grew 55.1% due to the leveraging of higher organic revenue along with a gain on disposal associated with the sale of certain books of business.
Income before income tax margin increased 580 basis points, growing faster than EBITDAC, driven primarily by amortization and intercompany interest expense growing at a slower rate than EBITDAC.
Moving over to slide number 10.
Our National Programs segment increased total revenue by 14% and organic revenue by 13.3%.
Regarding outlook for the last two quarters of 2021, we wanted to highlight that we anticipate approximately $4 million to $6 million of revenue shifting from the third quarter to the fourth quarter due to renewal timing for certain accounts.
EBITDAC increased by $7.9 million or 12.6%, growing slightly slower than total revenues due to incremental costs associated with onboarding new customers, increased non-cash stock-based compensation, and slightly higher variable cost.
Income before income taxes increased by $18.4 million or 38%, growing faster than EBITDAC, primarily due to lower estimated acquisition earn-outs payable and lower intercompany interest expense.
Over to slide number 11.
The Wholesale Brokerage segment delivered total revenue growth of 17.7% driven by acquisitions in the past 12 months and organic revenue growth of 12.3%.
EBITDAC grew by 19.1% with a margin increase of 40 basis points, even with lower guaranteed supplemental commissions, slightly higher variable operating expenses, and incremental non-cash stock-based compensation.
Income before income taxes grew by 6.9%, which was slower than total revenue growth primarily due to higher intercompany interest expense and a change in estimated acquisition earn-out payables.
Our Services segment increased total revenue and organic revenue by 4.6%.
For the quarter, EBITDAC grew by 9.8% driven primarily by leveraging organic revenue growth.
Income before income taxes increased by 19.8%, growing faster than EBITDAC due to lower intercompany interest expense and amortization.
We experienced another strong quarter of cash flow generation and have delivered $466 million of cash flow from operations through the first six months of 2021, growing $50 million or 12% as compared to the first six months of 2020.
Our ratio of cash flow from operations as a percentage of total revenue remained strong at 30.2% for the first six months of 2021.

Summary:
Our net income per share for the second quarter was $0.49, increasing 44% on an as-reported and adjusted basis, with the latter excluding the change in estimated acquisition earn-out payables.
For the second quarter, we delivered total revenue growth of $128.5 million or 21.5% and organic revenue growth of 14.7%.
Net income increased by $42.5 million or 43.9% and our diluted net income per share increased by 44.1% to $0.49.
For the second quarter of this year and last year, the impact was minimal with the adjusted and as-reported diluted net income per share of $0.49 growing 44.1% over the prior year.