The phrase "and the decline in the number" is correct and usable in written English.
It can be used when discussing a decrease in quantity or frequency of something, often in a statistical or analytical context.
Example: "The report highlighted the concerns regarding the economy, particularly and the decline in the number of job opportunities available."
Alternatives: "and the reduction in the number" or "and the decrease in the number".
Yet the growth in support for third parties and the decline in the number of marginal seats mean that hung parliaments and coalition governments have become more likely.
The cuts and the decline in the number of high-paying business passengers because of a threat of delays caused by the dispute will cost the company as much as $350 million in revenue this quarter and $250 million next quarter, Delta said.
The accountability office noted that the rate of workplace injuries — there were 4 million in 2007, including 5,600 fatalities — has declined fairly steadily since 1992, which OSHA attributed to improvements in workplace safety and the decline in the number of manufacturing jobs.
The challenges of drug development, including increasing costs, late-stage drug failures, and the decline in the number of drugs being approved by the US Food and Drug Administration over time, have generated interest in adaptive study designs that have the potential to address these problems.
And the decline in the number of people jobless six months or longer is not necessarily great news.
This resignation may reflect fewer women in the high echelons of medical hierarchy and the decline in the number of women applying to the top level of the PC system.
The decline in the number of tournaments in the U.S. corresponds with the decline in the number of highly ranked Americans and the growth of tennis in Europe and Asia.
The decline in the number of trained herd managers.
The decline in the unemployment rate occurred because of a decline in labor-force participation, not because of a decline in the number of unemployed.
"We see a decline in homeopathy in the NHS and we see a decline in the number of homeopathic hospitals.
Between 2011 and 2015, there was a 25percentt decline in the number of bull fiestas.
