5 Unpaid claims and claim adjustment expenses

The liability for unpaid claims and claim adjustment expenses as of 31 December is analysed as follows:

A reconciliation of the opening and closing reserve balances for non-life unpaid claims and claim adjustment expenses for the period is presented as follows:

The Group does not discount liabilities arising from prospective property and casualty insurance and reinsurance contracts, including liabilities which are discounted for US statutory reporting purposes. Liabilities arising from property and casualty insurance and reinsurance contracts acquired in a business combination are initially recognised at fair value in accordance with the purchase method of accounting.

Prior-year development

In 2015, claims development on prior years was driven by favourable experience on most lines of business. In particular liability, within the casualty line of business, showed a consistent level of releases throughout the year and across all regions. Favourable development on more recent accident years more than offset increases for US asbestos and environmental losses. Following large commutation and positive claim experience, accident and health claims developed favourably, contributing to the overall positive claims development on casualty. This was partially offset by the motor line of business, which experienced adverse trends in the US on most recent underwriting years. The European motor claims were also adversely impacted following improvements to the reserving models for French and German business. On property, claims development was favourable across all regions. Similar to last year, specialty lines showed a favourable trend. Experience has been significantly below what was expected, enabling reserves to be released.

A summary of prior-year claims development by lines of business is shown below:

US asbestos and environmental claims exposure

The Group’s obligation for claims payments and claims settlement charges also includes obligations for long-latent injury claims arising out of policies written prior to 1986, in particular in the area of US asbestos and environmental liability.

At the end of 2015 the Group carried net reserves for US asbestos and environmental liabilities equal to USD 2 094 million. During 2015, the Group incurred net losses of USD 128 million and paid net against these liabilities of USD 173 million.

Note that during 2015, USD 76 million of existing reserves were reclassified as asbestos following a detailed review of historic cedent accounts by our claims department. The above mentioned incurred amount (USD 128 million) does not show this amount as incurred during 2015.

Estimating ultimate asbestos and environmental liabilities is particularly complex for a number of reasons relating in part to the long period between exposure and manifestation of claims, and in part to other factors, which include risks and lack of predictability inherent in complex litigation, changes in projected costs to resolve, and in the projected number of, asbestos and environmental claims, the effect of bankruptcy protection, insolvencies, and changes in the legal, legislative and regulatory environment. As a result, the Group believes that projection of exposures for asbestos and environmental claims is subject to far less predictability relative to non-environmental and non-asbestos exposures. Management believes that its reserves for asbestos and environmental claims are appropriately established based upon known facts and the current state of the law. However, reserves are subject to revision as new information becomes available and as claims develop. Additional liabilities may arise for amounts in excess of reserves, and the Group’s estimate of claims and claim adjustment expenses may change. Any such additional liabilities or increases in estimates cannot be reasonably estimated in advance but could result in charges that could be material to operating results.