WCAS employs a specialist approach to generate operational improvements in our portfolio companies. Each of our Resources Group Functional Specialists has an area of expertise such as human resources, revenue/pricing, procurement, audit and capital markets. They work with our portfolio company management teams and Investment Professionals to implement specific operating initiatives and best practices across our portfolio. Our Resources Group Generalist Professionals each cover approximately two or three portfolio companies and leverage the expertise of Functional Specialists. The overall goal is to provide Fortune 500 corporate services and expertise to middle market companies. In addition, our Senior Industry Executives and affiliated Former CEOs possess deep industry expertise and relationships, enabling them to assist with deal sourcing and due diligence as well as strategic planning within our portfolio companies.
Throughout the year, WCAS hosts approximately 15 conferences, webinars and workshops for specific portfolio company executives. These events enable attendees to learn from industry experts, enhance their networks and exchange best practices with other portfolio companies.
WCAS believes its operational focus serves as the catalyst for superior value creation. To date, WCAS Resources Group initiatives have generated over $230 million in annualized run-rate EBITDA improvements for prior and current WCAS portfolio companies. The run-rate EBITDA improvements have been generated across the major areas of our Resources Group's toolkit, namely procurement, pricing and human capital.
The coordinated efforts of the Firm's Investment Professionals, portfolio company management teams and Resources Group have yielded strong operating results within the WCAS portfolio. WCAS X, WCAS XI and WCAS XII portfolio companies are projected to generate 2015 aggregate revenue and EBITDA of $17 billion and $2 billion, respectively, representing annual organic growth rates of 12% and 18%. WCAS believes that the portfolio's strong operating performance will drive its future investment performance.