The Office for National Statistics has today released its “Vital Statistics” report for 2015. It records that 777,165 babies were born in the UK in 2015. With 602,000 people dying, the “natural increase” in the UK’s population (excluding migration) was 175,000 people.
This number of births puts our current total fertility rate (TFR) at 1.8. TFR is the average number of children a woman of childbearing age would be expected to have in the UK at current birth rates. A TFR of 2.1 is considered the “replacement rate” at which numbers of births and deaths will balance out in time. The UK’s TFR has not been above 2.1 since 1972 but “population momentum” and net immigration have led to a population increase of nearly 10 million people since then.
Population momentum arises because the number of women of child-bearing age in the population reflects the higher birth rates of previous generations – as there are more of them, they produce more babies overall, even though the number of births per woman has fallen. Only when TFR has been at replacement rate for decades in a stable population do the numbers of births and deaths actually become equal. This is why further reducing the size of families is still required to limit population growth. The 2015 TFR for the UK is also higher than it was at any point between 1992 and 2005.
The UK’s death rate (number of deaths per 1,000 people) has fallen from 12.1 in 1972 to 9.3 in 2015. In addition to birth rates and migration, death rates are the third factor in determining population.
The UK’s total fertility rate is significantly below the global average of 2.5. According to the United Nations Population Fund, the country with the highest TFR is Niger, at 7.5, while Portugal’s TFR is 1.2 and Italy’s 1.5. Global average TFR has been falling since the 1960s but in the least developed countries, remains almost double the replacement rate at 4.0. Disturbingly, in some African countries the reduction in fertility appears to be stalling.
While the total fertility rates of developed nations are far below those in many developing nations, the environmental impact of each individual in high-consuming richer countries is far greater. A UK citizen is responsible for 40 times the CO2 emissions of a person from Sierra Leone. In emissions terms, the 777,000 little Britons born last year are equivalent to more than 30 million babies there.