The phrase "a declining number" is correct and usable in written English.
It can be used to describe a situation where the quantity of something is decreasing over time.
Example: "The report highlighted a declining number of participants in the annual event over the past five years."
Alternatives: "a decreasing number" or "a diminishing number".
Mr. Murphy, 48, is one of a declining number of actors whose name alone can get a movie made.
School district and city leaders say a declining number of families and children in the city will have repercussions beyond the schools.
"We are always in need of more skin," Ms. Gallo said, adding that the skin bank is now facing a declining number of donors.
As schools fight over what, due to a demographic blip, is a declining number of students, the device you get has become a keen area of competition.
Multiple providers offer mobile phone services to a growing number of subscribers, while a declining number of households use landline telephones.
Like most, Sewanee has a declining number of students paying full tuition, and a rising number who pay a discounted rate.
In Argentina itself, a nation historically seen as more Europeanized than its neighbors, the church is grappling with a declining number of Catholics who regularly attend mass.
Even so, Mr. Platt said in a telephone interview, falling star salaries and a declining number of films have made it easier to round up an ensemble.
The data displays a trend of gradually declining number of mental health clients per capita over the period of study.
They're both long-running British institutions faced with declining numbers, a lack of public investment, an innate hatred of daylight, and are in perpetual misery.
They're both long-running British institutions faced with declining numbers, a lack of public investment, an innate hatred of daylight and perpetual misery.
