decline

describes a decline that is both quick and significant

describes a decline that falls very quickly

a downturn in the economy of a country or region

a decrease in the number of people living in an area

describes a decline that is very sudden and steep

a worsening of ethical standards or behavior

used to state when or where a decline happened

used to describe the gradual loss of power, prosperity, or influence of something, like an empire or civilization.

used to specify what is declining (e.g., a decline in sales)

in a state of becoming worse, weaker or less in number

similar to 'in decline', often used for trends

to make a situation better after it has been getting worse