Ten weeks of demonstrations in the financial hub have seen millions of people take to the streets, increasingly violent clashes breakout between hardcore protesters and police and, more recently, flights grounded at the airport.

The rallies that began in opposition to a bill allowing extraditions to mainland China have morphed into a broader bid to reverse a slide in democratic freedoms.

Researchers from four of the city's universities surveyed participants across 12 protests -- including mass rallies and "fluid" and "static" demonstrations -- between June 9 and August 4 and found 54 percent were male and 46 percent were female.

Overall, 77 percent of the 6,688 respondents said they had a tertiary (higher) education, with 21 percent saying they had a secondary (high school) education.

The 20-29 age bracket was the most represented with 49 percent, compared to 11 percent under 20 and 19 percent aged between 30 and 39. Sixteen percent were 40 and above.

Exactly half (50 percent) considered themselves to be middle class, while 41 percent said they were "grassroots".

When asked why they were demonstrating, 87 percent said they wanted the extradition bill to be withdrawn, 95 percent expressed dissatisfaction with police's handling of the protests and 92 percent called for the establishment of an independent commission of inquiry.

The survey, called 'Onsite Survey Findings in Hong Kong's Anti-Extradition Bill Protests' was published on August 12 and led by researchers from the Chinese University of Hong Kong, Lingnan University, the Hang Seng University of Hong Kong and Hong Kong Baptist University.