Measure how demand responds to a change in premium rate.
输入需求量变动率与保费变动率,求需求弹性。
| Item | Formula / Rule | Source / Standard |
|---|---|---|
| Elasticity definition | Premium elasticity of demand = percentage change in quantity over percentage change in premium, a dimensionless ratio | Marshall 1890, Principles of Economics, Book III |
| Elastic response | When the absolute elasticity exceeds one, a rate increase shrinks premium income while a cut raises it | Varian 2014, Intermediate Microeconomics, Ch. 14 |
| Inelastic response | Below one in absolute value, a rate increase lifts premium income but can raise lapse rates | Varian 2014, Intermediate Microeconomics, Ch. 14 |