The bar chart illustrates the American household numbers of five different annual income ranges in 2007, 2011, and 2015.
Overall, the lowest number of households was within the $75000-$99999 bracket in all the three years examined, while that of the highest income group generally dominated and changed the most over the course.
Regarding households earning no more than $49999 per year, the quantity of those making less than $25000 per year was consistently lower than that of the $25000-$49999 cohort over the timeframe. Specifically, in 2007, the former accounted for a quarter billion households, about 2 million lower than the latter, both then increased to 29 and 30 million, respectively in 2011, before decreasing to 28 and 29 million, in that order in 2015.
Concerning the two next income bands, while the number of families earning $50000-$74999 annually stabilised at just over one-fifth billion over the period, that of the $75000-$99999 group fell minorly from just below 15 million in the first year to 14 million in the middle year and recovered to 15 million in the last year.
As for the range exceeding $100000, almost 30 million families fell within this range in 2007, which was the highest, with a subsequent marginal decline to approximately 28 million over the next 4 years, and peaked at roughly 33 million in 2011, surpassing its initial level to remain the highest group.