The phrase "a reduction in number" is correct and usable in written English.
It can be used when discussing a decrease in quantity or amount of something, such as population, resources, or items.
Example: "The study showed a reduction in number of species in the area over the past decade."
Alternatives: "a decrease in quantity" or "a decline in numbers."
This may be due to longer work hours in the U.S. A reduction in number of work hours/week, however, has been shown to be associated with reduction in emotional exhaustion, not only among U.S. residents [ 23- 25], but also in a cohort of Norwegian physicians [ 26].
However, at the structural level a reduction in number of synaptic vesicles in the pool has been reported in synapsin-1 and synapsin triple-knockout mice42,43.
They accepted the American emphasis on verification procedures, leading toward a reduction in number and yield of tests, with an eventual ban.
In addition, these mosaics show non-autonomous effects on surrounding wildtype cells, consisting always in a reduction in number of non-mutant cells.
The multiple correspondence analysis demonstrated that pain was clustered with a reduction in number of steps taken and a reduction in contact-seeking behavior.
Dozens of judicial buildings are due to go up for sale as the coalition pushes through its rationalisation of the courts service with a reduction in number by 142, including 93 magistrates courts.
After the election, with the change in administration, instead we've seen a curtailment, a reduction in numbers.
Clegg said on Sunday that the government's immigration policy would lead to a "reduction in numbers" but did not "pursue a fixed numerical target".
By comparison, this year's World Cup coverage has seen a reduction in numbers on the 295 who staffed the South Africa tournament in 2010.
There have been some problems in terms of a reduction in numbers of part-time students, but in some ways that is more to do with the recession than the funding environment.
Elimination is therefore not a control option, nor is a reduction in numbers exposed likely to be practicable.
