The given chart depicts the figure for households in the United State by their yearly earnings in three different years (2007, 2011, and 2015).
Upon initial observation, it is clear that the number of US households by annual income at $100,000 or more was the highest in the most surveyed time. Another noteworthy feature is that all the number of households by yearly income changed in trend while that of households at $75.000-$99.999 remained unchanged.
Starting in 2007, the number of households with incomes $100,000 or more was approximately 30 millions, that of households at less than $25.000 and $25.000-$49.999 were 25 millions and nearly 27 millions, respectively. In 2011, while the figures of households with incomes less than $25.000 and $25.000-$49.000 increased slightly to 29 millions and 30 millions, respectively; that of households with incomes $100.000 or more dropped minimally from 29 millions to 27 millions. Then in the final year, 2015, the surveyed experienced a small decreased in the figures of households with incomes less than $25.000 at 28 millions and $25.000-$49.999 at 29 millions, in contrast, that of households with the highest incomes ($100.000 or more) grow significantly and reach a peak of 33 millions.
From 2007 to 2015, the figures for households with incomes $50.000-$74.999 remained unchanged at nearly 21 millions, while that of households with earnings $75.000-$99.999 saw a slight decrease from 14 millions to 13 millions before a small increase to 15 millions in 2015.