Good morning, everyone. Thank you for joining us. My name is Melanie Hill, and I'm the Head of Investor Relations at Australian Ethical. I would like to begin by acknowledging the traditional owners of the country on which we work, the Gadigal people of the Eora Nation, and recognize their continuing connection to the land, waters, and culture. We pay our respects to their elders, past, present, and emerging. Please note that today's presentation is being recorded, and a recording will be made available on the Australian Ethical website. Slides used in the presentation are also available on our website. There will be an opportunity for Q&A at the end. Questions can be submitted via the webcast using the Ask a Question box. We may also have media in attendance this morning.
I'm joined this morning by John McMurdo, CEO and Managing Director of Australian Ethical, and Mark Simons, our CFO. John will go through the business highlights, Mark will cover off the financials, and then John will give an update on investment performance and business strategy. I'll now hand over to John.
Thanks, Mel, and good morning, everyone. Before I turn to the many highlights from the past six months, I'd like to first thank the Australian Ethical team for their ongoing hard work. Their commitment to investing for a better world is, in my opinion, unparalleled. At our half-year results in August, we announced an aggressive high-growth strategy to leverage our leadership position and expand market share where we see the most potential. We outlined four key strategic pillars we'd be investing in and pursuing to strengthen our business for both impact and growth. You can see those on the slide. Pleasingly, we're seeing this investment already pay dividends in the form of many of the highlights Mark and I will cover this morning. We've seen our positive momentum continue and finished the 2021 calendar year in strong shape. In particular, headline growth remained strong.
Operating revenue increased 38% to AUD 35.2 million, up from AUD 25.6 million for the six months ended December 31, 2020. Meanwhile, net inflows were AUD 600 million, 42% above the prior corresponding period. Combined with positive investment performance, this saw us reach AUD 6.94 billion in funds under management at December. At the core of our business are the investment returns we deliver for our growing customer base, and on this front, it's been another strong period of performance. The team, led by our CIO, David Macri, have continued our enviable track record of delivering long-term performance for investors in both our superannuation options and managed funds.
In addition to our existing products, we also launched two new managed funds in October, followed by our first ever ETF earlier this month, as demand for quality ethical investment solutions continues to grow. Awards, accolades, and recognition over the past six months have been many and varied. On the industry front, we were identified as a responsible investment leader twice by RIAA, while at a product level, we won more awards for both our managed funds and superannuation. In a sign that we are truly starting to see mainstream brand awareness, we were named among Australia's top 100 most trusted brands by Roy Morgan, and our new brand identity was awarded one of the creative services industry's highest accolades. Now, I'd like to pause there for a moment and discuss the significance of this on two fronts. The first is the value of mainstream brand awareness.
Because if we're to realize our purpose of investing for a better world for people, planet, and animals, it's imperative that we reach audiences that go beyond your stereotypical ethical investor. We must make ethical investing for everyone. The second point I'd like to make is about trust, which has become an ever more important strategic advantage in our sector. There was a time the financial services sector didn't value such a soft factor, rich in emotional nuance, but this has never been our position. For us, trust has always been the gold standard of brand attributes. For more than three decades, our customers have trusted us with their financial security, and it's something that we have never taken for granted. Right now, we're seeing the financial services sector rush to elevate the role of governance and trust on the organizational agenda.
A question many of them will be asking themselves will be how to best create and then maintain trust. The answer, our answer, is authenticity. The Australian Ethical Foundation, for example, is an unequaled expression of our authenticity. It receives 10% of our profits, which it allocates to charitable, benevolence, and conservation causes. Its goal is to find and then fund the most effective charities and solutions addressing climate change and other important world issues. As such, we were proud to have announced the recipients of our first Visionary Grants Program and unleash the potential of early-stage, high-impact climate solutions. Then in December, together with Giving Green, we launched a guide to help Australians identify and donate to the highest impact ways to fight the climate crisis.
While we do this for genuinely altruistic reasons, in accordance with our constitution, it's another proof point of our authenticity that sets us apart from others. Authenticity is deeply reflected in our investing, a point of difference and competitive advantage that's hard to imitate. Because I'm not talking about just one or two ethical investment options, but an entire portfolio dedicated to making a positive impact for people, planet, and animals, supported by an entire business dedicated to investing for a better world. During the period, we released our sustainability report, which aligns directly with our business strategy, proving that it's not only possible to pursue both business objectives and sustainability objectives together, but it's essential. Mark, can I hand to you to update on the financials?
Thanks, John, and good morning, everyone. John has already run through some of the key highlights, and so I'd like to focus on some of the other pleasing financial results. As John mentioned, our operating revenue was up 38% to AUD 35.2 million. This strong revenue growth was driven by strong average fund growth of 47%, partially offset by the impact fee reductions that took place in June and October 2021. Net profit after tax attributable to shareholders was up 5%. Underlying profit after tax was up 12% after excluding last year's one-off revenue items. While we have strong revenue growth, operating expenses have increased at a higher rate as we reinvest into our business in line with our high-growth strategy. Total operating expenses are up 45% to AUD 27.4 million, which reflects this strategic investment.
It's pleasing to see how our strategy is yielding strong flows and fund growth and driving top-line revenue growth. An interim dividend of AUD 0.03 per share has been declared. Despite some challenging market conditions, we saw strong growth in FUM to AUD 6.94 billion, up 38% on first half 2021, and 14% up since June 2021. This FUM growth was driven by solid net flows and positive investment performance for the period. Our advisor channel now makes up 20% of our FUM and totals AUD 1.4 billion. Advisor net flows grew significantly during the period. They're up 135% versus the same period last year. It is great to see this channel growing rapidly as we invest in distribution capability and marketing to drive this important channel.
The direct channel remains our predominant channel, contributing 74% of FUM, and it continues to see strong growth. On a product view, our managed funds are growing faster than our super fund as we continue to develop and actively market these products. Customer numbers have grown by 22% over the calendar year to over 76,000. Managed funds customers increased 32%, and super fund members expanded by 20% off a larger base. Platforms FUM grew 59% during the period, noting that each platform is regarded as only one customer. Our products are available on 24 platforms. Net flows remained strong, and we have seen a growing trend over the past three comparative periods. In the first half, managed funds net flows were up 37% to reach AUD 2.23 billion, a 129% increase when excluding institutional flows.
During the period, we saw a single institutional managed fund redemption of AUD 50 million, which impacted our overall managed fund flows growth rate. Institutional FUM currently represents only 6% of our total FUM. In super, our net flows were AUD 0.37 billion, a 45% increase over last year. We are pleased to continue to have one of the lowest super outflow ratios in the industry, a result of our focus on customer engagement as well as acquisition. We have customers who love what we stand for and know that their money is doing good. Our average revenue margin for the calendar year 2021 was 1.02% following fee reductions, down from 1.07% in the prior year. We've landed at the end of the year at a revenue margin of 0.99%.
Our fee strategy continues to focus on ensuring ethical investing is as accessible and competitive as possible. Our fees are reviewed annually, and we continue to make strategic fee reductions to share the benefits of scale with current customers, along with the expectation that this investment will assist with attracting new customer flows in an increasingly competitive market. While ensuring our fees are competitive, we believe returns and impact are even more important. Both managed funds and super have been strong contributors of our 38% revenue growth. Our first half operating expenses increased 45% as we invest in our strategic growth priorities. Employee costs increased 40% as we made key strategic capability hires in our investment team, sales team, data and technology team, and the new innovation team.
Hires were also made in our in-house contact center and finance teams to support the growth in the business. Five of the new hires were strategic project contractors to support our strategy implementation. The increase in employee costs also reflects the full year run rate of hires in FY 2021, as well as the remuneration increases following a remuneration review. Fund-related expenses have increased as a result of higher fund and customer numbers. It is worth noting that the uplift in fund-related expenses of 23% is lower than volume growth due to the reduction in super admin fee rate following insourcing the contact center and the scalable nature of some of the fixed managed fund administrator costs. This is partially offset by cost of constant regulatory changes and the new strategic asset allocation cost to uplift this function.
Our drive to lift our brand awareness and grow our distribution channels saw an increase in brand and marketing costs. The increase in external services costs was driven by investment in a number of strategic initiatives in relation to the new mobile app, launch of new products, build out of our cloud-based back office platform, and M&A due diligence costs. Overall, we remain confident that we can deliver strong value for our shareholders and other stakeholders through this strategic investment in the business. We continue to strengthen our balance sheet with no debt and a strong cash position. The increase in regulatory capital is the result of building up retained earnings and has covered the recent Sentient Impact Group investment. In volatile market conditions, we are comfortable to hold more regulatory capital than might seem necessary. We've been through many of the next two slides.
However, it is worth noting the strong compound annual growth rates referred to as CAGRs across all metrics. Our fund has grown at four-year CAGR of 28%, and our profit has grown at a CAGR of 26%. I now hand back to John to run through the investment and business update.
Thanks, Mark. Our investment performance has remained strong despite the volatility seen in markets around the world, the ongoing persistence of COVID, the inflationary pressures, and of course, escalating political tensions. For our super customers, our MySuper option returned 5.2% for the six months, outperforming its benchmark by a full 1% and ranked second against its peers over the three-year period. It was also the second-best scoring option for investment performance across the country in APRA's MySuper, Your Future, Your Super comparison, which was a seven-year comparison test, and we were the only retail fund to make the top 10. For our managed fund customers, our Australian Shares Fund continued its enviably long track record of outperformance. The wholesale fund returned 5.3% during the period, outperforming its benchmark by 1.3%.
Our Emerging Companies Fund, meanwhile, has outperformed the benchmark for all time periods, and the wholesale fund returned 7.7% over the six months. As the volatility continues, we remain focused on our ethical investment philosophy, looking beyond the short-term volatility and maintaining a long-term outlook. It's an approach that has continued to deliver strong long-term returns for our customers. I began this morning by recapping on our strategic pillars as we shared at our full year results last year, and they are the backbone of the high-growth strategy we're pursuing. I referred to them in the past, and the opportunity ahead of us as a once-in-a-lifetime business opportunity. Now, I wanna update you on some of the important strategic milestones we've reached during what has been a very busy and productive half year period for Australian Ethical.
The Australian Ethical team's been effective and efficient in delivering really important strategic milestones during the half year period. Starting with principled investment leadership, returns have remained strong, as we've shared. We launched in October our High Growth and High Conviction funds, and earlier this month, we launched our first ever ETF. This clearly gives us a new product, but also we believe helps us access a new segment, a fast-growing market segment in ETFs. We've hired capability into the team to build out our strategy and proposition into the institutional and charity markets. Our investment in Sentient Impact Group lifts our ability to deliver to customers wanting even higher impact investments and also demonstrates our greater strategic interest in M&A for both capability and for scale.
We've bolstered our investment committee with the appointment of three new highly experienced non-executive investment committee members who will be announced to the market before the end of this month. As advocates for a better world, we announced a more ambitious net zero target for the private investments in our portfolio and allocated AUD 500,000 to innovative climate solutions via our foundation. In November, we extended our brand presence internationally when we put the names of more than 7,500 Australians on the front page of the Financial Times during COP26 in Glasgow as eyes open globally to the climate risk we all face. We've been proactive in growing awareness of our positive impact across a range of mediums, including television.
The early uplift we're seeing in brand awareness is promising, and I look forward to sharing data on this over the next few months. While we enjoy leading customer satisfaction, we have continued to invest in the capability of our contact center, both human and technology capability. We are also taking important steps towards delivering a frictionless and connected, compelling client experience. I'm pleased to confirm that we will be launching a customer app later this financial year, initially for our managed fund customers, in response to what is quickly becoming a very digital savvy customer base. This is being supported by the digital transformation of back-office systems to cloud-based scalable technologies. Our channel expansion has also progressed strongly with a broadened advisor distribution team, enabling the uplift in flows that Mark spoke to earlier. It's pleasing progress, and it is what we said we would do.
We've shared previously what we think the opportunity is, which is to build a business 3x or even 5 x the scale it has been. We've made a promising start, and with the right sequenced investments into the right facets of our business over the next two or three years, we remain convicted that this is possible to the benefit of all of our stakeholders. Again, my sincere thanks to all the team at Australian Ethical for their continuing hard work. We've made a very strong start to the year with pleasing growth, and we find ourselves tracking ahead of timelines on various strategic projects. We are mindful of market conditions. Even with restrictions easing, the sweeping impact of Omicron shows that sentiment around the pandemic can still shift quickly. While inflationary pressures and political tensions are a front-of-mind concern for investors, even as we sit here this morning.
As an investment business, we are of course leveraged to the markets, and we do expect short-term volatility to continue. However, and notwithstanding those market conditions, we have every confidence to continue with our high growth strategy. As such, we anticipate continuing the quantum of investment during the second half with resources deployed in growth areas as identified in our business strategy. We remain well positioned to benefit from regulatory, policy, market, and other investor tailwinds that remain in full effect on a medium-term view. Our confidence to succeed comes from the quality of our people, our ethical investing pedigree, our financial strength, and the continued success we are achieving in executing our strategy. Thanks for being with us this morning, everyone, and Mark and I are happy to take questions.
Well, thank you everyone. We have no questions today. A reminder again, the presentations and the webcast will be on our website. Thank you. Have a good day.