The annual tradition of Pro Bono Week offers another excuse to recognize a form of volunteering that is uniquely powerful for both giver and recipient. Falling this year in the week between October 23rd and 29th, Pro Bono Week is a global campaign that celebrates and activates pro bono service across all professions that use their talents to make a difference.

Taproot Foundation, an organization that connects nonprofits and social change organizations with skilled volunteers who share their expertise pro bono, has built Pro Bono Week into a worldwide initiative that promotes pro bono services and encourages ever more companies and individuals to get involved throughout the year.

When you take a closer look at the benefits of pro bono services, it becomes clear why this type of volunteering has become the fastest growing domestic volunteer program over the past three years.

Pro bono volunteering is arguably the most impactful of all types of volunteering, and it is is indisputably the most economically valuable. Last year, Taproot worked with corporate philanthropy firm CECP to update the Pro Bono Valuation Guide, the first ever set of standards for assigning monetary value to pro bono services. The two organizations looked at a range of data supplied by the 2015 Salary Guides on average starting salaries (excluding benefits, bonuses, or other incentives) for accounting and finance, administrative, technology, legal, and creative professionals produced annually by Robert Half. The dollar values reflect average, national hourly rates of pay, adjusted for consulting, for multiple professions across three levels of experience – early level, mid-level and executive.

Here’s what they found: the average per hour value of pro bono service is $150, an increase from $120 as found in 2009. This compares to an estimated hourly value for traditional volunteer time of $23.07, as per data from the 2014 Bureau of Labor Statistics.

That’s quite a difference.

Further, CECP’s 2016 Giving in Numbers report found that companies that offer skills-based volunteer programs, regardless of what other domestic program they offer, had the highest volunteer participation rates. When companies offered a board leadership program, which is a form of skills-based volunteering, the volunteer participation rate was the highest – at 35.9%. Formal pro bono services programs yield the second-highest volunteer participation rates, at 35%.

The bottom line is that when employees are offered the opportunity to engage in skills-based volunteering, they’re more likely to volunteer. Furthermore, their involvement in this type of volunteering is a proven opportunity for skills and leadership growth. Data by Deloitte suggests that 67 percent of pro bono project participants gained new subject matter knowledge and 55 percent indicated they gained new client service skills.

This helps explain why the percentage of U.S. companies offering pro bono services increased from 43% in 2013 to 54% in 2015, and internationally increased from 17% to 24%. In 2015 alone, more than half of all companies offered pro bono service programs.

Points of Light, a nonprofit dedicated to increasing volunteer service, recently released The 2016 Civic 50: Turning Good Intentions into Sound Business Practices, which honors the 50 most community-minded companies in the nation each year as determined by an annual survey. Honored every year at Points of Light’s Conference on Volunteering and Service, The Civic 50 is a roadmap for how companies can turn good intentions into sound business practices.

The most recent report recognized many companies that are engaging in skills-based and pro bono services.

Many Civic 50 companies are repurposing the skills of their workforce to help maximize the social impact of their community involvement. While this requires more planning and investment, an average of 22 percent of Civic 50 volunteer hours are now skills-based, a slight increase over the 2014 figure of 20 percent. Talent development is another reason that Civic 50 companies focus on skills-based volunteering, with nearly 50 percent of companies offering a formal enterprise-wide program to develop skills using community involvement programs, up from 46 percent in 2014.

The Civic 50 report echoes the findings of Giving in Numbers regarding the elevated focus on impact. As businesses shift their relationships with communities from “donor to a charity” to “partner in solution,” and with companies increasingly integrating community involvement into their business functions, impact measurement has become a more important priority for companies. Seventy-eight percent of Civic 50 companies formally measure the social impact of at least one aspect of their community involvement.

In an effort to tackle complex, large-scale social issues, many companies are partnering with organizations in structured, long-term ways. Skills-based volunteering is a key feature of this form of collaboration to achieve systemic change. When you put employees at the center of a company’s social purpose efforts, particularly in a way that leverages their skills for maximum impact, the benefits to the company and community multiply exponentially.

Learn how top companies are putting pro bono power into action by downloading our full (free) report here.