Respiratory products maker Fisher and Paykel Healthcare said its net profit dropped by 28 per cent in the March year as earnings returned to more normal levels following a bumper, Covid-driven 2021.

The company said that after an "unprecedented" 2021 financial year, the company's performance was again strong, with operating revenue 33 per cent above the pre-Covid 2020 financial year.

Total operating revenue for the 2022 financial year was $1.68 billion, down 15 per cent,

The company's net profit after tax was $376.9 million, a 28 per cent decline from the previous financial year, or a 30 per cent decline in constant currency terms.

The net profit and revenue figures were in line with market expectations.

F&P Healthcare's share price rocketed up to a peak of $37.68 in August 2020 on the back of Covid-19 demand for its products.

While it has since drifted back to more sedate levels, last trading at $21.71, the company is still the NZX's biggest by market cap at over $12 billion.

According to World Heath Organisation data, the rate of Covid infection around the world has fallen sharply since January.

The company's products were in hot demand from hospitals all around the world in response to Covid-19, which attacks people's ability to breathe.

Managing director and chief executive Lewis Gradon said that over the last two financial years F&P Healthcare had supplied $880m of hospital hardware, the equivalent of about 10 years' hardware sales prior to Covid-19.

"The growing body of evidence supporting the use of nasal high flow and our other respiratory therapies shows that our products have a clear role to play in improving care and outcomes beyond Covid-19 patients," he said.

"We have a proven fifty-year track record of changing clinical practice and now we have the additional benefit of customers already having our hardware and clinical experience with its use," he said.

F&P Healthcare increased its final dividend by 2 per cent to 22.5 cps.

The total dividend for the year rose by 4 per cent to 39.5 cents.

Directors also approved a profit-sharing payment totalling $19m for the 2022 financial year to be paid to employees who worked for the company for a qualifying period.

In the Hospital product group, which includes humidification products used in respiratory, acute and surgical care, revenue was $1.21b, a decline of 19 per cent.

In the Homecare product group, which includes products used in the treatment of obstructive sleep apnea (OSA) and respiratory support in the home, revenue was $469.5m, a 1 per cent increase over the previous financial year.

Gross margin decreased by 59 basis points for the year to 62.6 per cent, or a 147 basis points decline in constant currency terms.

High air-freight use and elevated freight rates continued to weigh overall compared to pre-Covid-19 rates, impacting constant currency gross margin by about 240 basis points.

"During the second half of the 2022 financial year, there was a sharp peak for our hospital consumables sales in December, followed by a low in February," the company said.

Hospital consumables subsequent trading to date was exhibiting a slow recovery from February.

The company did not give an earnings guidance for the current year given "ongoing uncertainties regarding our customers' stockholding choices".