LONDON (Reuters) - Global property catastrophe reinsurance rates will fall 5% to 15% on Jan. 1 for books of businesses which have not suffered losses, reinsurance broker Guy Carpenter said on Monday, as the market becomes more competitive after years of rate rises.

Reinsurers insure the insurers, and have raised prices and excluded some business in recent years following increased losses from wars and natural catastrophes. However, reinsurers have become more willing to take on risk after enjoying strong profits, Guy Carpenter, a unit of Marsh McLennan ( MMC ) said.

"Renewal outcomes at year-end reflect reinsurers' positive property experience over the last two years," Dean Klisura, president and CEO of Guy Carpenter, said in a statement.

However, insurance portfolios which have faced catastrophe losses in the United States, Europe and Canada will see unchanged rates, or rises of up to 30%, Guy Carpenter added.