Much of Europe
A country with an aging population typically has a population growth rate that is low or negative, as the proportion of elderly people increases relative to the younger population. This demographic trend can result in challenges such as a shrinking workforce, increased healthcare costs, and pressure on social systems.
Nigeria
Yes, in a mathematical sense a growth rate is defined as a rate of increase in a series over time. Thus if the series is declining over time, or for a period, the growth rate is negative. In a semantic sense, it is probably better to refer to 'contraction' rather than 'negative growth', but it is not incorrect to use the latter terminology.
when country have discovers oil, its get money which effect in increases in population growth, which ultimately increase population growth rate
Bangladesh
Growth in population, and in growth rate, can be caused by many factors. For example, it might indicate improved health amongst citizens, such as by higher birth rate and/or increased years in life. A population growth can also be caused by immigration. Growing industries that need workers can attract new residents to a country, increasing its' population. Such growth from immigration may also result from negative factors, too. For example, persons in a country affected by war, famine or oppression may flee to another nearby country, increasing the total population in that new country.
A negative population growth exists
Poor
France. It's not increasing but it's not decreasing.
If the population growth rate becomes zero the population size becomes static. It stays where it was when it became zero until the rate changes. If the rate becomes negative the population would begin to shrink.
germany