Shares in healthcare provider Metlifecare plunged 9 per cent, 49c to $5.01, after it reported a December half year net loss of $12.3 million.
Last year under different accounting rules, it reported a net profit of $14.6m. Its property was valued down by $10.7m.
The company said themain driver for the result came from the new international accounting rules that meant unrealised property revaluation gains or losses had to be included.
Previously, revaluations were recorded in reserves and only realised gains or losses were recorded in the income statement.
The company said its reported profits would now be strongly influenced by the underlying property market.
"It is important to note that the cash flow of the business is not affected by a change in accounting standards."
The company delivered a cash operating surplus of $12.9m for the period.
It declared an unimputed dividend of 11c per share, up 10 per cent on a year ago.
Independently-prepared valuations of the group's investment property resulted in a gross investment property value of $1.232 billion at December 31, down from $1.243b at the beginning of the period.
The company said the property valuation was "essentially flat" and reflected a flat residential housing market over the same period and was "therefore not unexpected".
"It should also be noted that there was an exceptionally strong revaluation gain of $117.2m for the comparative half-year period to December 2006."
During the period the company acquired Merivale Retirement Village in Christchurch to bring the number of lifestyle villages it operates to 16.
At the end of this period Metlifecare had 2385 villas and apartments.
