The bar chart shows the number of US households in five income groups in 2007, 2011 and 2015. Overall, the number of households earning less than $50,000 increased slightly during the period. The middle income groups stayed almost unchanged, while households earning $100000 or more showed the biggest growth in 2015.
Looking at the lower income groups, households earning less than $25,000 increased from about 25 million in 2007 to around 29 million in 2011, before falling a little to approximately 28 million in 2015. In the same way, the number of households earning between $25,000 and $49999 rose from roughly 27 million to 30 million in 2011, then decreased slightly to about 29 million in 2015.
As for the middle-income categories, the figures changed very little over the years. Households earning between $50,000 and $74,999 stayed stable at around 21 million in all three years. Similarly, the $75,000-$99,999 category remained close to 14-15 million households throughout the period.
By contrast, households earning $100000 or more followed a different trend. The figure was around 30 million in 2007, then dropped slightly to about 28 million in 2011. However, by 2015 it increased significantly and reached approximately 33 million households, which was the highest figure on the chart