The income elasticity for most staple foods, such as wheat, is known to be between zero and one.

As incomes rise over time, what will happen to the demand for wheat?
What will happen to the quantity of wheat purchased by consumers?
What will happen to the percentage of their budgets that consumers spend on wheat?
All other things equal, are farmers likely to be relatively better off or relatively worse off in periods of rising incomes?

all other things equal

The income elasticity of demand measures how changes in income impact the quantity demanded of a particular good or service. In the case of staple foods like wheat, which have an income elasticity between zero and one, it means that the demand for wheat is income inelastic.

When incomes rise over time, the demand for wheat will increase, but at a slower rate compared to the increase in income. This implies that the quantity of wheat purchased by consumers will also increase, but not as proportionately as their income.

Since the percentage of the budget spent on wheat remains relatively stable despite rising incomes, consumers are likely to allocate a smaller portion of their budget towards wheat. This is because as incomes increase, people tend to spend a smaller proportion of their budget on basic necessities like food.

In periods of rising incomes, farmers are likely to be relatively worse off. This is because the income elasticity of demand for staple foods like wheat is less than one, meaning that the demand for wheat does not increase in the same proportion as income. As a result, farmers may not experience a significant increase in the prices they can charge for their wheat, while facing potentially higher input costs and competition.