Population...

There are only 5 million people still alive.

Many of the shots killed people and stopped women from having children. At that point there were 50 people living. Slowly the population grew to 500,000 and scientists discovered how to clone people, and every person was cloned a few times and the population grew to 4,000,000 and all the people discovered that the same scientists made the formula that killed lots of people so they killed the scientists. Little did they know that that was the worst mistake they had ever made.

See Ya!
Cellis