Use this sociology calculation to reproduce a named demographic, inequality, mobility, urban, or survey measure when the population, period, categories, and coding rules are explicit.

Later census

Required number. Cohort counted in the later census.

Earlier census

Required number. Same cohort counted in the earlier census.

Survival ratio

Required number. Intercensal survival ratio applied to the starting cohort.

The cited overview of Sociology supplies background for the terminology and domain context used by this tool.^[1]

Isolate net migration as the census count minus the survivors projected forward from the earlier census. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

Net migration

Returned number. Net migration implied by the census difference; negative means net emigration.

• Definitions, sampling error, missing data, historical context, geographic boundaries, weighting, and classification choices can materially change social indicators and their interpretation.
• Later census must be at least 0.
• Earlier census must be at least 0.
• Survival ratio must be at least 0.
• Use finite inputs in the displayed units, preserve source measurements and assumptions, and independently verify consequential decisions.

Report the source population and uncertainty, inspect disaggregated data, and compare multiple accepted indicators rather than treating one summary statistic as a complete social explanation.

• Survival Ratio Census Method Calculator

  Compare a birth cohort across two censuses to estimate its five-year survival ratio.

• Ravenstein Gravity Flow Index Calculator

  Rank migration potential between two places with the gravity model product of populations over squared distance.

• Gross Migration Stream Total Calculator

  Sum every off-diagonal origin-destination cell of a square migration stream table into gross migration, excluding non-movers on the diagonal.