Stop the benefits given to kidless unemployed couples and unemployed couples having kids. A couple that does not have the finance to support the expenses of the kid should not be allowed to give birth to a child or to further children. There are many parents in this world who inspite of having poor financial condition or under addiction of gambling, alcohol and drugs have given birth to 1 or more children and then forced their children to beg on the streets, on the trains or made the children work in farms or fireworks factory or as house servants or forced girl child into prostitution by selling that girl child to brothel owner. There are many unemployed men in this world addicted to alcohol, drugs and gambling who will marry and treat wife as a slave, physically abuse her, make her do any work outside and grab her income.
Population can be reduced due to natural disasters or nuclear accidents.
In many Indian states, the ratio of female to male is very low as illegally sex of unborn child is determined, if that sex is a female then the child is aborted before birth-reasons like dowry related torture after marriage, rape and sexual abuse are responsible for such actions. As number of females have declined, birth rate has declined and men are having problem finding a wife.
Union territory of Daman and Diu had a sex ratio of only 618 females per 1000 male as per 2011 census of india. Indian state of Haryana had sex ratio of 879 females per 1000 males and child-sex ratio of 834 girls below age 6 to 1000 boys below age 6 as per 2011 census of india.
Government and ministers, educational institutes, corporate, ngo, social workers, celebrities, sports-persons, artists, police, lawyers and all top-position and educated people through self-example have to create more awareness even to the most rural parts of the world on the importance of family planning, population control and improving the financial condition to meet the expenses. Unfortunately one past central government minister from India himself was a father to 11 kids-9 girls and 2 boys. If such type of person is the minister of a country then forget about population control.