Stocks and work in progress are valued at the lower of cost and net realisable value after making due allowance for obsolete and slow-moving stocks. Cost includes all direct costs and an appropriate proportion of fixed and variable overheads. Work-in-progress is reflected in the accounts on a contract by contract basis by recording turnover and related costs as contract activity progresses.
Construction contracts
Where the outcome of construction contracts can be reliably estimated, contract revenue and contract costs are recognised by reference to the stage of completion of the contract activity as at the year end.
Where the outcome of construction contracts cannot be estimated reliably, revenue is recognised to the extent of contract costs incurred that it is probable will be recoverable, and contract costs are recognised as an expense in the period in which they are incurred.
When it is probable that total contract costs will exceed total contract revenue, the expected loss is expenses immediately, with a corresponding provision for an onerous contract being recognised.
Where the collectability of an amount already recognised as contract revenue is no longer probable, the uncollectible amount is expensed rather than recognised as an adjustment to the amount of contract revenue.
The entity uses the percentage of completion method to determine the amounts to be recognised in the period. The stage of completion is measured by reference to the contract costs incurred up to the end of the reporting period as a percentage of total estimated costs for each contract. Costs incurred for work performed to date do not include costs relating to future activity, such as for materials or prepayments.