Study the following extract on country Y’s population data and answer the questions that follow.
The population of country Y in 1970 was 60 million. From 1971 to 1975 the total number of births was 25 million and deaths stood at 3 million. 8 million immigrants and 4 million emigrants were recorded in the reporting period.
(a) Present the above data in a table.
(b) (i) Determine the net migration within the period.
(ii) Calculate the population of the country in 1975.
(c) What is the percentage increase in the population of the country from 1970 to 1975?
Explanation
(a) Country Y's Population data
| year | No. of Death in Million | No. of Death in million | No. of 1mm. in million | No. of Emm. in million | Total population in million |
| 1970 | - | - | - | - | 60 |
| 1971 - 75 | 25 | 3 | 8 | 4 | 86 |
OR
| year | 1970 | 1971 - 75 |
| Number of births in millions | - | 25 |
| Number of deaths in millions | - | 3 |
| Number of immigrants in millions | - | 8 |
| Number of emigrants in millions | - | 4 |
| Total population in million | 60 | 86 |
(b)(i) Net Migration = immigrants — Emigrants
8 million — 4 million = 4 million
(ii) Total population in 1975 = 1970
population + Net Migrations + (number of births — number of deaths)
60 million + 4 million + (25 million — 3 million)
or
64 million + 22 million. = 86 million.
(c) Percentage increase
New population — old population x 100
Old population
86 million - 60 million x 100
60 million
26 x 100 = 43.33%
60
\(\frac{1200 x 100} {15,000 * 1}\) = 8% for B