Hong Kong (CNN) In just five years there's been a sixfold increase in Hong Kong's so-called McRefugees -- residents who spend their nights sleeping in 24-hour McDonald's outlets across the city -- a survey has found.

The study, conducted by the non-profit Junior Chamber International (JCI) Tai Ping Shan , counted 334 people sleeping in McDonald's restaurants during June and July, a significant increase since a similar study in 2013, which found only 57 sleepers.

"The purpose of this research was originally to provide services (for the sleepers), but we found that there is no specific picture of the McRefugee situation in Hong Kong," Jennifer Hung, chairwoman of the study, told CNN. "They (government officials) acknowledged that there are no statistics, so we conducted this research."

Researchers who visited 110 of Hong Kong's 24-hour McDonald's outlets found not all of the overnight sleepers were homeless.

More than 70% of respondents said they had other places to sleep, such as public housing flats or subdivided units, and the majority had either full-time or part-time jobs, challenging the common perception that these sleepers are homeless or unemployed.

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