Abstract |
Intercensal growth rates for Botswana were calculated from census data for 1964 and 1981, because of the reported inaccuracies in the 1971 census; the extent of undercounting in 1971 was computed. Adjustments were made for mortality levels in 1964 and 1981 and fertility in 1971 and 1981. Intercensal growth rates between 1964 and 1971 were found to be 3.6% versus 4.7% for the de facto population and 3.2% versus 4.1% for the de jure population. The possible interpretations were an undercount in 1971, an overcount in 1981, or a rapid growth rate. Plausible interpretations were an undercount and a faster growth rate. Reliability is expected in the 1964 census, because it was based on a household canvass under British rule. 1981 census data were considered to be well planned and executed under the guidance of the UN. Procedurally, the following estimation techniques were performed: undercounts of the <5-year old population were smoothed out in 1964; the 1981 exponential growth rate was used to derive the 1971 population; general sex ratios were used to determine the 1971 sex distribution; 1981 mortality was adjusted through inflation by 1.13 to account for increasing the reference period from 323 to 365 days; Brass's Growth Balance Method was used to assess the accuracy of mortality i 1981; 2 and 4 parameter logit life-table methods were used to derive the level of mortality and ratio of child-to-adult mortality; the orphanhood and child survivorship methods were used to estimate mortality in 1964 from mortality in 1971 and 1981; hybrid life tables were constructed; and the P/F ratio method and the Relational Gompertz fertility model were used to correct and estimate total fertility rate for 1971 and 1981. The results total fertility rate for 1971 and 1981. The results showed an undercount of 14% and a female undercount of 7% for the 1971 data. Males were undercounted the 3 most in the de jure population. In the forward projections of population for 1971, undercounting of those <15 and >15 years old was greater for females. For those >15 years old, undercounting was greater in males than in females. But the overall discrepancies for females was still lower than for males. Estimation with forward adjustments showed a growth of 3.09% for the de jure, 3.08% for the female, and 3.10% for the male population. Forward projections from 1917 reveal growth rates of 3.33% for total, 3.30% for female, and 3.36% for male population. |