Although small businesses in general continue to climb back to their pre-pandemic level of sales, a recent national survey found the smallest firms are still hurting.

Small-business sales as a whole have reached 80 percent of pre-pandemic levels, according to a recent survey conducted by Kabbage, a fintech company that provides funding to small businesses. That average is primarily supported by medium-size and large small businesses, which Kabbage defines as companies with 21 to 500 employees.

But for the smallest businesses–firms with fewer than 21 employees–sales remain hobbled. The survey, which was conducted between May 27 and June 24, noted that the smallest businesses regained just 55 percent of pre-pandemic sales, putting into perspective their path to recovery, which gravely contrasts that of their larger peers, according to the survey.

“It’s clear that as Covid restrictions lift across the nation and Americans’ lives largely return to a new normal, the economic effects among the smallest of small businesses linger,” says Kathryn Petralia, co-founder of Kabbage, which is owned by American Express. 

Beyond sales, Kabbage’s survey also underlined the challenges small-business leaders are facing in dealing with vaccination protocols. With 67 percent of the respondents reporting they were fully vaccinated at the time of Kabbage’s survey, that’s higher than the country as a whole: The Centers for Disease Control and Prevention reported that 60.6 percent of the adult population in the U.S. was fully vaccinated as of August 2. 

Even before the recent spike driven by the Delta variant, many small-business owners were requiring non-remote employees to be vaccinated. And 34 percent of small-business leaders said they would require customers to show proof of vaccination before entering their facilities maskless, similar to what bars and restaurants began doing in San Francisco last week. The question of whether to require vaccines is just one of many issues that will continue to confound businesses during this time of uncertainty, notes Petralia. “As customer demand rebounds and businesses’ doors reopen, all small businesses must navigate new economic and local challenges that affect their path to return to growth.” 

Hiring has been another challenge. Filling an open role can take eight weeks or longer, according to the survey. Of the business owners surveyed, 26 percent have tied their labor issues to extended unemployment benefits and stimulus payments, which they say is a disincentive for potential job seekers–but some economists have taken issue with that assertion.

These hiring concerns come at a time when businesses are busier online and during non-business hours. One result: Owners are working longer hours, according to the survey, with some reporting working three to six more hours a day than before the pandemic to keep up with the incoming business.

Depending on how you look at it, that could be a good problem to have.