MUNICH, May 22 (Bloomberg) — Hannover Re, the world's fourth-biggest reinsurer, had its credit outlook raised to "stable" from "negative" at Standard & Poor's, which cited the company's strong operating performance.Standard & Poor's affirmed its credit rating on the Hanover, Germany-based company at "AA-," the fourth-highest rating among 10 investment grades, the rating company said in an e-mailed statement yesterday.

The company operates as a subsidiary Hannover Re (Bermuda), a class 4 reinsurer set up on the Island in 2001.

"The outlook revision reflects the group's very strong operating performance, strong enterprise-risk management and very strong competitive position," Standard & Poor's credit analyst Hiltrud Besgen said in the statement.

The stable rating outlook means S&P is less likely to change its rating on the company in the near future.