Population Analysis & Projections: Age-Band Profiles, Birth & Death Rates, Migration, Cohort Projections and Dependency Ratios

What you'll build

What you will be able to do

Each lab ends with a concrete result that you build yourself and the checker confirms, cell by cell.

• Turn the population counts of a fictional district into shares and cumulative shares by five-year age band, find the band that holds the median resident, measure the 65+ share and draw the age profile.
• Turn five years of birth, death and moving counts into rates per 1,000 residents, see that natural increase can be negative while the district still grows, and pool a rate over several years.
• Roll the population forward with the balancing equation, compare the result with the register count, and split five years of growth into natural change and net migration.
• Look up a fictional five-year survival ratio for each band, move every cohort into the next band for 2031, handle the open 85+ band and total the survivors.
• Estimate five years of births from fictional rates per 1,000 in the bands 15–49, turn them into the new 0–4 band, spread net migration over the bands with a fixed profile and total the projected 2031 population.
• Repeat the survival step four times to reach 2046 without migration, follow one cohort through twenty years, total the population and track the 65+ share as an ageing indicator.
• Read a fictional central projection for 2026, 2036 and 2046, calculate young and old-age dependency ratios with SUMIFS and turn the school-age population into the classes the district will need.
• Add three fictional migration scenarios to the zero-migration base, compare twenty-year growth, measure the spread between the scenarios and chart them as lines.