"times of decline" is correct and can be used in written English.
It is typically used when referring to a period in which something is becoming less important or successful. For example, "During times of decline, it is important to remain optimistic and work towards bettering the situation."
Or not always: the Church, he said, "has experienced times of brilliance," but "has lived also times of decline in its ability to think".
Just as surely as the economic cycle will present times of decline and contraction, growth will come again.
Adaptive allocation, or adaptive investing, was introduced to remedy the fallacies within traditional buy-and-hold methods and maximize a portfolio's return in up markets while protecting during times of decline.
Religious energies and programs, we read often enough, lower their standards and get in trouble in times of decline and demoralization.
When censored children were excluded, we found dramatically shorter times of decline, validating this expectation.
It is unclear why the study by Roberts et al. (2001), which excluded censored children, reported longer median times of decline.
In times of declining resources, this principle translates into increased efficiency and optimum use of any kind of waste and co-products.
The alluvial records fit well with proxy precipitation records, and the main aggradational periods correspond to times of declining monsoonal strength.
In times of declining oil reserves, new methods for serinol synthesis or its derivatives are needed.
This is a message which comes in times of declining public interest in the political process as it was known in the twentieth century.
Conducting successful science on a shoestring budget makes for a good story but it is, more importantly, a vital skill set in times of declining research funding.
