Band 6+: the chart below shows the number of households in the US by their annual income in 2007, 2011 and 2015. Summarise the information by selecting and reporting the main features and make comparison where relevant.

The bar chart presents the annual revenue of households in the US in three different years, in 2007, 2011 and 2015. Overall, it can be seen that both low and high earning group saw an increase over the years, while mid-earning group remained relatively unchanged.

In 2007, the majority of households who earned above $100,00 or more annualy were around 29 million, whereas approximately 14 million people earned between $75,000-$99,000. Following this, the highest-earning group experienced a slight decline to about 27 million people, before surging to over 33 milliom in 2015. In contrast, the lowest-earning group slightly fell to around 13 million in 2011, reaching 15 million in 2015.

Furthermore, residents who earned between $50,000-$74,999 remained essentially unchanged over the years, while lower revenue families fluctuated. Families who earned less than $25,000 and between $25,000-$49,999 saw an increase to about 27 and 29 million in 2011, before decreasing about 2 to 3 million in 2015.