Credit card delinquencies were on the rise during the second quarter as investors continue to watch for signs of a consumer slowdown.

But Goldman Sachs' economics team dug into the corporate results of 26 retailers and found spending might not be slowing where one might expect as pressures mount on American wallets.

"Perhaps surprisingly, we find that the lower-income consumer is outperforming," Goldman Sachs senior economist Spencer Hill wrote in a note on Sunday night.

Goldman Sachs split sales data from retailers into three categories based on the median income of companies' customers. Goldman found stores with lower-income consumers (those with household incomes from $62,000 to $85,000) saw same-store sales increase 5.6% compared to last year in the second quarter. Those stores include the likes of Walmart (WMT) and Ross Stores (ROST), as well as dollar store chains Dollar General (DG), Dollar Tree (DLTR) and Five Below (FIVE).

On the other end, retailers with higher-income consumers (median income between $96,000 and $128,000) saw same-store sales decline 2.2%. Those stores included Bloomingdale's (M), RH (RH), Lululemon (LULU), and Nordstrom (JWN).

The analysis fell in line with credit card data Goldman Sachs tracks that showed consumer spending has increased 25% since the start of the pandemic in lower-income zip codes. Meanwhile, spending in middle-income (+22%) and higher-income zip codes (+16%) has increased at a slower pace.

Goldman Sachs expects this gap to narrow a bit during the current quarter and through the end of the year as other macro headwinds weigh on the consumer.

"One key question is whether management guidance appropriately embeds the expected drag from resuming student loan payments, which we expect will weigh on upcoming retail sales and consumer spending reports," Hill wrote.

In August, Bank of America released an analysis of its card spending data from the start of the year through July. The data showed higher-income spending had been weaker than lower-income spending on a month-over-month basis for four of the first seven months of the year. BofA attributed part of that divergence to the labor market where higher-income individuals are seeing wages increase at a slower pace while more of the cohort is applying for unemployment benefits.

Investors will get another update on consumer spending Thursday with the August retail sales report slated for release. Economists surveyed by Bloomberg expect retail sales increased 0.1% in August, a noted decrease from the 0.7% jump seen in July.

Josh Schafer is a reporter for Yahoo Finance.

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