The given graph illustrates the number of families in the USA classified according to their annual earnings at three time points: 2007, 2011 and 2015.
Overall, there is an upward trend at all five income levels listed over the examined period, with the number of homes with $100,000 or more standing at the highest positions and those with $75,000-$99,999 taking the last level at both the beginning and end of the period.
It is evident that the figure of families with income less than $25,000 and $25,000-$49,999 similarly experienced a slight fluctuation over the period, starting at 25 million and 27 million respectively, then both rising to around 30 million before ending up at the point of approximately 28 million. In contrast, there is no fluctuation in the figure of homes earning $50,000-$74,999 yearly, stabilizing at 21 million.
On the other hand, the highest and lowest number of households labelled by annual income shared an identical pattern with a small decline in 2011 before reaching a higher position by the final year. While families making $100.000 or more started nearly 30 millions the experienced a decline of 2 million in 2011 and finally reach the highest point of the chart at 33 million, those making $75,000-$99,999 saw a slight drop by 1 million to 14 million in the middle of the period and rebounded to reach 15 million in 2015.