Page 49 - Nien giam 2019
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Population density   =   Population (persons)
                                                     2
                                                                                  2
                                         (persons/km )         Territorial area (km )
                             Sex  ratio  of  the  population  reflects  number  of  males  per  100

                        females. Sex ratio of the population is determined by the following formula:
                                          Sex ratio     =    Total of males   × 100
                                      of the population     Total of females

                             Crude  birth  rate:  The  indicator  measures  the  fertility  of  the

                        population, is one of the two components of natural population increase.
                        High or low value of crude birth rate can affect the size, structure and
                        population  growth  rate.  Crude  birth  rate  indicates  that  for  every  1,000
                        people, how many live births are in the reference period.

                                                             B
                                                    CBR =      1000
                                                             P

                             Where:

                             CBR: Crude birth rate;

                             B: Total live births in the reference period;

                             P: Population up to the reference time-point.
                             Total fertility rate (TFR) reflects the average number of live births

                        that  would  be  born  per  woman  (or  a  group  of  women)  during  the
                        childbirth period if the woman (or a group of women) passes age-specific
                        fertility  rates  observed  in  a  given  reference  period  during  the
                        reproductive period (aged 15 to 49).

                             In case the specific fertility rates are calculated by age groups (age-
                        interval of each group is 5 years) then index “i” expresses 7 age groups,
                        including:  15-19,  20-24,  25-29,  30-34,  35-39,  40-44  and  45-49.  Total
                        fertility rate is calculated by the following formular:


                                                            7  B
                                                 TFR   5     i   1000
                                                           i 1  W i



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