Migrants who can't afford to buy property in Beijing are finding themselves cash-starved as at least 40 percent of their salary goes to landlords, a new report said.

The report was jointly released on Tuesday by Beijing University of Technology, the Social Development Committee of Beijing and the Social Science Academic Press.

The average salary stood at 56,061 yuan a year in Beijing in 2011, while rent in Dongcheng District, a relatively expensive area, was 40,896 yuan on average, taking up 72.9 percent of the salary. The proportion was 66.4 percent in Chaoyang District, with rent at 37,200 yuan. The figure was 43 percent in Changping District, a suburb known for its affordable lifestyle.

Those who don't have a Beijing hukou, or permanent residency, suffer from the increasingly unaffordable rents in the city, since 89.6 percent of permanent residents own property, said the report.

Stringent curbing measures held back non-permanent residents from buying property in the capital, while sky-high housing prices made it an even remoter dream, forcing them to struggle in the rental market.

The city's housing conditions didn't keep up with the pace of its economic expansion, the report concluded.