The amount of money paid by the public health authorities to the North West Independent Clinic in Ballykelly has fallen substantially over the past three years.
Pay-outs to other private health providers have also fallen.
In 2013/14, £11.7m was paid to the Ballykelly hospital.
But this diminished to £7.7m in 2014/15 and further to just £2.5m in 2015/16.
Payments to the North West Independent Clinic were dwarfed by those made to the Belfast-based 3fivetwo group although its receipts from the public health authorities also fell back over the three year period.
3fivetwo received a substantial £30.6m in 2013/14.
This fell to £22.5m in 2014/15 before dropping to £13.3m in 2015/16.
The Ulster Independent Clinic, also Belfast-based, received £700,000 from the public purse in both 2013/14 and 2014/15 but just £7,000 last year.
The Health Minister Michelle O’Neill released the details to the West Tyrone Ulster Unionist MLA Ross Hussey.
Despite the apparent reduction in pay-outs to the three private health care providers identified by the Minister, expenditure on private operators is growing in other areas of health.
Last week this paper reported how the use of the private sector for homecare provision rose steadily in the Western Trust over the past five years.
In 2011/12, the Trust spent £12,179,000 independent or private home care providers but last year that figure had grown to £18,679,000.