Good morning, good afternoon, welcome to the SS&C Technologies, Inc. Annual Meeting of Shareholders. I would now like to introduce the first presenter, Bill Stone.
Good morning, and welcome to SS&C Technologies Holdings' 2021 Annual Meeting of Stockholders. I'm Bill Stone, Chairman of the Board of Directors and Chief Executive Officer of the company. In light of the recent public health concerns related to COVID-19, we are holding this year's annual meeting of stockholders through this virtual format. At this time, I would like to introduce our Board of Directors. I'm pleased to introduce Normand Boulanger, Smita Conjeevaram, Michael Daniels, Jonathan Michael, David Varsano, and Michael Zamkow. We also have other members of the company's management team who are here in attendance with us today, including Rahul Kanwar, President and Chief Operating Officer, Patrick Pedonti, Senior Vice President and Chief Financial Officer, Joseph Frank, Senior Vice President and Chief Legal Officer. Also joining today's meeting are representatives of PricewaterhouseCoopers, which is SS&C's independent registered public accounting firm.
Before we commence the formal portion of the meeting, I would like to touch on two housekeeping matters. First, if you are a shareholder of SS&C and wish to submit a question, you may do so during the meeting by typing the question into the box at the bottom left-hand of the screen. You must have logged in using your unique control number to submit a question. After we give an overview of the items of business being considered at this meeting, we have allocated approximately 10-15 minutes to answer submitted questions from shareholders relating only to those items of business.
If you have any questions related to SS&C, not specifically related to the items of business covered at the meeting, or if your submitted questions are otherwise not addressed, you can reach out to SS&C's investor relations department at InvestorRelations@sscinc.com, and those questions will be answered in a timely manner. Second, if you're a shareholder of SS&C that logged in using your unique control number, you can also vote your shares during the meeting by clicking on the Click Here button on the bottom right-hand side of your screen. If you have already voted your shares, there's no need to vote again during today's meeting unless you would like to change your vote. The agenda for the meeting should be visible on the top right side of your screen, and a link to the rules of conduct is available under the Meeting Materials section of the screen.
We intend to strictly follow the agenda and rules of conduct to carry out the business of this meeting. In accordance with the bylaws, a copy of the notice of annual meeting of stockholders proxy statement and formal proxy has been presented to all stockholders. As Chairman of the Board of directors of the company, I have been provided with an affidavit from Broadridge Financial Services establishing that notice of this meeting was duly provided in accordance with the bylaws. The voting list of stockholders is available for inspection as provided by the company's bylaws. These documents will be filed with the corporate records of the company. As we've done in past years, the formal meeting will be conducted first, after which I will make a few remarks about SS&C's and financial performance during the past year.
Following my remarks, I will answer shareholder questions about today's meeting, as well as about SS&C's business. Please note that any remarks that we make today about future expectations, plans, and prospects for SS&C constitute forward-looking statements under the federal securities laws. Actual results may differ materially from those indicated by these forward-looking statements as a result of various important factors, including those discussed in the Risk Factors section of the most recent annual report on Form 10-K, which is on file with the SEC and available on our website. SS&C has appointed Broadridge Financial Services to act as inspector of election for this meeting, and Tracy Oats, a representative of Broadridge, is participating in today's meeting. Ms. Oats has signed her oaths of office, which will be filed with the records of this meeting.
I have been informed by the inspector of election that the holders of 239,893,703 shares of common stock of the company are present in person or by proxy. This represents approximately 93.82%, which constitutes the majority of the total issued and outstanding shares of the common stock of the company entitled to vote at this meeting. Based on that report, I declare the quorum is present and that this meeting is duly constituted and convened and is competent to proceed with the transaction of business. Mr. Frank, Chief Legal Officer, will serve as secretary of the meeting and will prepare the minutes of the meeting. As indicated in the proxy statement, there are three proposals to be acted upon at this meeting. Proposal one is to elect the following nominee as a Class II director for a term scheduled to expire in 2024 annual meeting, Jonathan E. Michael.
Proposal two is to approve an advisory vote, the compensation of our named executives. Proposal three is to ratify the selection of PricewaterhouseCoopers LLP as our independent registered public accounting firm for fiscal 2021. Each of these proposals is more fully described in the proxy statement, and each is recommended by the board of directors. There are no other proposals to come before this meeting since our management has not made any other proposal, and no other proposal were submitted by stockholders in the manner prescribed in the company's bylaws, which require certain information concerning stockholder proposals be provided to the company before the date of this meeting. The polls are open for voting on three matters that have been presented. If you have already voted, you need not vote again at this meeting.
If you have not voted, or if you would like to change your vote, you may do so by clicking here, button on the bottom right-hand side of your screen. We will attempt to answer stockholder questions submitted through the web portal relating to items of business being voted on at this meeting after my remarks concluding the voting. As a reminder, you must have logged in using your unique control number to submit a question. It is now 9:07 A.M. and the polls are open for voting. We will pause for one minute to allow stockholders who wish to cast their vote to do so. Since all stockholders have had adequate time to vote, it is now 9:08 A.M., and I hereby declare that the polls are now closed. Will Mr. Frank please present the preliminary results of the voting?
Thank you, Mr. Chairman. The preliminary results from the Inspector of Elections are as follows. With respect to proposal number one, the election of a director, a plurality of the votes cast have been voted for the election of this year's nominee. With respect to proposal number two, the advisory vote to approve of the compensation of our named executive officers, a majority of the votes cast has been voted for the proposal. With respect to proposal number three, the ratification of PricewaterhouseCoopers LLP as independent registered public accounting firm of the company for fiscal 2021, the majority of the votes cast have voted in favor of the proposal. I turn the meeting back over to you, Mr. Chairman.
Thank you, Mr. Frank. Based on a preliminary report from the Inspector of Election, each person nominated for election as director has been elected to serve as a director until 2024 annual meeting. The advisory vote on the compensation of our named executive officers has been approved, and the audit committee selection of PricewaterhouseCoopers LLP as independent registered public accounting firm for fiscal 2021 has been ratified. These actions will be recorded as stated in the minutes of this meeting. This concludes the formal matters to be acted upon at this meeting. I declare the meeting closed. I'd like to briefly discuss SS&C's business and financial performance. As you know, SS&C is a leading provider of mission-critical cloud-based software for financial services and healthcare industries. The reason we've been successful has been that we focus on expertise across the entire company.
We have a track record of delivering to the most sophisticated organizations in the world, in all types of financial services companies and in various healthcare companies. We also have been doing it for 35 years, we are a trusted and proven provider. Our strategy is simple: provide excellent customer service, deliver solutions to support clients' needs, leverage technology for innovative solutions and risk mitigation, and deliver real-time data and insights to our customers. When you look at SS&C and our value proposition, we start with that we're a technology company. Our clients process hundreds of thousands and millions of transactions every day. Having the right technology and being able to enhance and improve and innovate with that technology is a key competitive advantage. We also offer tremendous flexibility. One size does not fit all in the financial services or healthcare industries.
We need to be flexible, we need to be innovative, and we need to be nimble. We also think digitization is here to stay. Things are going to get faster. 5G is going to rapidly change how we use our mobile devices, and we believe that the ability to invest heavily in digital is a key component of our future. SS&C in 1986 did $86,000 in revenue. Last year, 2020, we did almost $4.7 billion in revenue. We have a proven ability to execute. We have 18,000 customers, and we're focused. We also don't just deliver technology and say, "Here it is." We do this through a consultative approach. We are experts. We help our clients deploy our software, build best practices, automate manual processes, and use the latest in technology to further their gains. Lastly, we're fully independent.
A lot of us are CPAs or old CPAs, and we believe in separation of duties and internal control. The more complex things get, the more value, different types of structures, the more you have to pay attention to your internal control systems and make sure that you've got doers and you've got checkers. SS&C helps our clients do this. As you look at the numbers around SS&C, 40 fund administrators, many of the biggest in the world, use our technology. Of course, we're the biggest fund administrator in the world. Now, 75 of the top 100 hedge funds use us. 95% of all municipal bonds structured in the United States use SS&C's DBC product. 99% of all the commercial paper issued is run on SS&C products. We have 41 million covered lives in total health. We paid almost $500 million pharmacy claims last year.
We're a big player in financial services, and we have a lot of technology, and we have a lot of very capable people. SS&C has used acquisitions throughout its history in order to gather more talent, expand our technology portfolio, add clients, add geographic dispersion, and strengthen the company. Our most recent acquisitions are Algorithmics from IBM in December of 2019, Donato in March of 2020, Innovest in May of 2020, and Capita in March of 2021. These four companies add to our capabilities, bring a tremendous amount of talent, and we expect to add new product and new service throughout the next several years. Our financial highlights in Q1, our revenue was up about 5%. Our operating income was up 7%. Our earnings per share was up 14.6%. This is during COVID-19 for the past year. I think your company has stayed focused.
We have paid attention to our employees and kept them safe. We have delivered for our customers. That's our job. We're strongly focused on shareholders. We understand you own the business, and we appreciate your faith in us. Our CAGR on cash flow has been 23% since 2016. In 2020, we did almost $1.2 billion. While that was down from $1.328 billion in 2019 had a one-time $250 million long-term license. Without that, 2019 would've been up over $100 million. We have an unrivaled portfolio of capability across derivatives, mortgages, real estate, global macro, paired trades, municipal bonds, just across a wide range. That gives us a lot of stability. We are what you call a sticky business.
We do not believe accounting's going away, we do not believe the taxing authorities are going away, and we don't believe the regulatory authorities are going away. SS&C solves problems for our customers, and that's what allows us to continue to grow. We're still primarily in the Americas, about 78%, but when you take a 22% on approximately $5 billion, you're talking about $1.1 billion that's outside the United States and Canada. Similarly, we write a lot of our contracts in US dollars, but we also have it in about 10% in British pounds, and we have about 7% in others, which would primarily be the euro, and Canadian dollar and Australian dollar. We have a high-margin business model. In 2020, we operated about a 40% margin, 2019 about 39%, 37% in 2018.
That dipped because we had bought DST Systems in April of 2018, and we've spent time moving them back up to our EBITDA margins. We also de-leveraged the company. When we buy big acquisitions, we de-lever as quickly as we can, which means we pay down a lot of debt. So far, we've gone from five times lever to 3.35x since the DST acquisition was announced, and we continue to pay off debt in 2021. We've had a 21% CAGR in adjusted diluted earnings per share since 2016. What that means is our earnings per share has gone from $1.64 to $4.30. In the first quarter, we did $1.18. Again, I appreciate all of you that came onto our annual meeting, and I would like to thank you for that. Now we can turn it over to any questions that anyone may have.
Given that there are no questions, I want to thank you for participating in SS&C Technologies Holdings' 2021 annual meeting of stockholders. We hope that everyone stays safe and healthy, and have a good day.
Thank you. The annual general meeting for SS&C Technologies Inc. has now come to an end. Thank you for attending. You may now leave the virtual meeting.