"in deteriorating" is a correct and usable phrase in written English.
You can use it to express the idea that something is getting worse or declining over time. For example, "The quality of her work has been in deteriorating in recent weeks."
That contempt has also been reflected in deteriorating quality.
If we hadn't legislated, the impact would have been felt in deteriorating community relations and in racists exploiting the issue.
Several isolated rural properties came under threat from a bushfire in the south of the state that intensified in deteriorating conditions.
Introduction: Respiratory rate (RR) is among the first vital signs to change in deteriorating patients.
In some congested areas, the number of vehicles that contend for the channel is high, which results in deteriorating the DCF performance.
This compound, derived metabolically from the shikimic acid pathway, inhibits the enzyme prolyl endopeptidase, which is involved in deteriorating certain neuropeptides that are believed to contribute to memory and learning.
Orthostathism may result in deteriorating cognitive function, gait instability, fatigue and generalized weakness [ 29].
The latter is notably present e.g. in deteriorating milk and meat products [ 44].
Over prolonged periods, this may result in deteriorating health status and greater downstream utilization of more costly services [ 22].
It is important to monitor health facility delivery, since decreasing utilisation could result in deteriorating health outcomes, including birth outcomes.
But as Walsh points out, increasing numbers of automobiles and other motor vehicles in developing countries will result in deteriorating air quality, greater congestion, and poorer quality of life.
