Recalling

Economics is the study of meeting unlimited human wants with limited resources.

<sigh>

By increasing the level of income of the people in the lower income range you can increase their expenditure. If you need to increase savings for the country to trade with then you’ve got to increase the income level of the well-to-do folks.

<Sigh>

Elasticity of demand
-1..……. 0………. 1

Anything at zero is perfectly inelastic
Anything that is infinite is very highly elastic (or perfectly)
> 1 relatively inelastic
< 1 relatively elastic
and it doesn't get below 0 because that would break the demand law

Cigarettes and alcohol + necessities have 0 elasticity. While luxury good may have very high elasticity

<now I feel like a total nerd>