From an IBM article:

Since adopting [DevOps], Nationwide has achieved a 90 percent on-time software delivery rate (up from 60 percent previously) and a 70 percent increase in users’ system availability. But what’s truly impressive is that, in concert with the increased pace of software delivery, Nationwide reduced critical defects 80 percent and high-level defects by 86 percent, which means the company is delivering higher-quality software faster. Nationwide says it can now “invest more into playing offense” to help the company drive innovation and build new offerings.

See the full-court case study as well.