Demographers studying the current population of a particular country produce the age-structure diagram shown in the figure below: Population pyramid for a country. The pyramids base shows that approximately 300,000 males and 275,000 females in the country are 0 to 5 years old. The pyramid becomes increasingly wider through its widest point, which shows approximately 440,000 men and slightly fewer women are 30 to 35 years old. The pyramid then becomes increasingly narrow; the levels for men become narrower than the levels for women. Which of the following conclusions is supported by this diagram?

There are currently several billion people living in the country.

Slightly more girls than boys were born during the past five years.

The birthrate has been steadily decreasing for the past 25 years.

The country experienced a population decrease between 30 and 35 years ago.