The Pew Research Center released a new analysis on Wednesday, reporting that low-income and high-income Americans combined now outnumber the Middle class. The report also said that Middle class Americans are “falling behind financially.”

According to CNBC, the report states that at the beginning of 2015, 120.8 million adults lived in middle-income homes while 121.3 million Americans lived in lower and upper income households. The study classifies middle class Americans as adults earning two-thirds to double the national median which is approximately somewhere between $42,000 and $126,000 a year for a three-person family.

The shift of the economic classes has been developing over the past few decades. According to the Huffington Post, the report states that low income American citizens have increased from 25% to 29% since 1971. Within that same time period, the upper class has risen from 14% to 21%. Meanwhile, the middle class has decreased from 61% to around 50%.

The Pew Research Center’s analysis also claimed that middle income Americans were making less money. The average income of middle class households fell by 4% between 2000 and 2014 and median wealth fell by 28% between 2001 and 2013.

This shift “could signal a tipping point,” according to the report.

More Americans are now starting to make more money and join the upper class, which the study notes as “economic progress.” However, the study warns that the upper class can make more money at a faster pace than the middle and lower classes, which can widen the gap between the different classes.