In New York City, subway delays are inevitable for every commuter to experience at some point in time, however, a new study shows that low-income New Yorkers are disproportionately affected by these all-too-common inconveniences.

According to the study, which was drafted by economists Nicole Gorton and Maxim Pinkovskiy of the Federal Reserve Bank of New York, roughly half of employed New Yorkers across the five boroughs rely on the subway to get to work each day. Using data from the American Community Survey (ACS) from 2012 to 2016, the study found that higher incomes are typically associated with shorter commutes, since people are willing to pay more for a shorter commute and prices tend to be higher near transportation centers. On the contrary, “communities in which most people take the bus tend to be poorer than the median.”

To prove its point, the study created two heat maps that highlight the correlation between income earnings and commute times.

“Spending more time on the train necessarily increases the risk of experiencing some kind of service disruption,” says the study. “[Su]ubway riders with the longest commute times are also less able to substitute away from a troubled line because the next subway line or station may be very far away.” This case in point has been proven by other studies that also found various savings on rent prices by moving further away from subway stations.

When it comes to subway delays, low-income New Yorkers are already likely to have longer commutes to work and the study found that they are often “less able to substitute away from a troubled line because the next subway line or station may be very far away.” As a result, unanticipated delays put these New Yorkers at risk of losing pay, potentially having less time to invest in their health and education, and possibly missing out on quality family time. Commuters who work during nonconventional hours (say, an overnight shift) are even more likely to have their subway rides affected by planned work.

Per the New York Post, New York City Transit Authority president Andy Byford caught wind of the study and responded by saying that the agency’s Fast Forward plan to overhaul the subway will make commutes better for all New Yorkers. “These programs are our ironclad commitment to improve service and ensure that our transit system continues to be one of the great equalizers for all New Yorkers,” he said in a statement.

Read the report in its entirety here.