The chart illustrates the number of households in the US divided into four income categories for the year 2007, 2011 and 2015.
Overall, it is evident that the number of households earning $100000 or more showed increased significantly over the period, while those earning less than 25000 experienced a steady decline. The Middle-income groups, including those earning $25000-$49000 and $50000-74000, showed minor fluctuations but generally remained stable.
In 2007, the number of households in the higher income category ($10000 or more) was approximately 28 million. This figure increased sharply to approximately 20 million in 2011 and further surged to about 30 million by 2015. Conversely, the lowest income category (less than $25000) started roughly at 25 million households in 2007, declined slightly to 28 million, and further decreased to 20 million by 2015.
Turning to middle-income households, those earning $50000-$74999 remained relatively stable between 2007 and 2015. Meanwhile, the $75,000-$99000 income groups saw a modest increase from approximately 13 million in 2007 to around 15 million in 2015, despite a minor dip in 2011.