The provided chart below depicts how the number of households in the US are categorized by their annual income, changed in the three years examined.
Looking from an overall perspective, it can be seen that the figures for the number of households from different income groups show no certain trend over the three examined years. While the lowest figure remains stable, the chart showed an alternating fluctuation between the two highest figures over the 3 years.
Looking at the chart more closely, it is readily apparent that the majority of the US earns more than 100.000 per year with 29 million in 2007, reduced by 2 million in 2011 and ended with a drastic rise to 33 million in 2015. Another major contribution is the number of households belonging to 25.000 - 49.999 income groups, which fluctuated around 26-30 million over all three years.
Regarding the three remaining figures, one can see that the below 25.000 income groups witnessed a remarkable change from 25 million in 2007 to approximately 29 in 2011, but ended up with a slight decrease to 28 million in the last year. In contrast, the figures for the 50.000 - 74.999 and 75.000 - 99.999 income groups showed a minute increase in their numbers, both fluctuating around 20 million and 15 million, respectively.
