The Effects of Change to Demand

There are a number of factors that can cause a change in the demand.  These factors include a change in the price of the product, the consumers' income, the price of related goods, the tastes and preferences of consumers, and the number of consumers in the market. 

When there is a change of one of the factors of there is a change in the demand curve. For example, if someone's income grows, then their demand for goods will increase, shifting their demand curve to the right. This will lead to a higher quantity being consumed at a higher price. But there can be a negative effect that shifts the supply curve to the left where a lower quantity is consumed at a lower price.

An example of this is my recent experience was this past christmas.  I received a christmas bonus just before christmas which increased my income for that month.  Then on boxing day when the prices of high end clothing goes down I now had a higher demand for more expensive items that are of sale for a lower price, due to the prices being lower but also the increase in my income.  This causes my demand for higher priced clothing items to increase or the demand curve to move to the right if it was charted.  (See example of the demand curve increasing - moving to the right in the image below)