Calm chief executive David Ko, speaking at the Fortune Brainstorm AI conference earlier this month, said his company conducted a survey of more than 250 C-suite executives, and posed a simple question to them: “How are you doing?”

“Most people said that they were doing good,” Ko said.

But when Ko broke down wellness metrics—whether leaders felt anxious, depressed, or mentally present at work—the results were starkly different: 48% of respondents reported feeling overwhelmed, while a quarter said they experienced anxiety or depression. Moreover, 34% said they were mentally drained, and 40% reported failing to be mentally present on the job. Half of the survey participants said they thought of stepping down from their positions.

Ko also asked executives to compare their energy to a battery, arguing it’s a more accessible metric for individuals to assess their mental health. Only one in four executives said their batteries were “fully recharged.”

“Most leaders, like in this room, are operating at about 20%,” Ko said. “Think about what that means.”

The cost of CEO burnout

Burnout, which the majority of executives of small to medium-size businesses report feeling, can not only result in leaders taking more sick days, higher absenteeism, and greater turnover, but can also gnaw at companies’ bottom lines. A study published by the American Journal of Preventive Medicine in April found burned-out workers can cost a workplace an average of $3,999 per hourly worker, and up to more than $20,000 per executive. The social contagion effect, in which employees pick up on the mood of their colleagues or superiors, can result in a “downward spiral” for the whole office, human resources experts said.

Ko said companies that have invested in mental health interventions report less burnout, higher return on investment, and greater engagement. Nearly 85% of individuals Calm surveyed reported believing mental health directly impacts a company’s bottom line.

The CEO said mental health interventions, such as using a mindfulness app like Calm, can help employees process AI anxiety, particularly amid growing concerns over AI displacing human workers. According to a Pew Research Center report from February, more than half of employees surveyed said they’re worried about the impact of the technology in the workplace in future. Calm, for its part, has integrated AI-guided meditations into its app, and Ko suggested his mindfulness app can not only alleviate AI anxiety through mindfulness, but also by having users engage with AI directly.

“In a world that’s currently being transformed by AI, organizations are realizing that our greatest assets aren’t just the technology,” he said. “It’s the people behind them.”