The average tax burden of respondents was 5.14 per cent of total business turnover in 2016, the academy said. That was slightly less than the average of 5.32 per cent in 2014.
It found that the combined costs and expenses of the companies surveyed had exceeded their combined revenues in the three years from 2014.
Respondents said rising costs were largely to blame, with raw materials up 7.8 per cent last year, labour costs rising 6.8 per cent, and rents up 9.7 per cent.
Although Beijing has promised to reduce company taxes and charges with a taxation regime overhaul and preferential policies for small firms, the government collected an extra 9.8 per cent in revenues in the first half – compared to GDP growth of 6.9 per cent in the same period.
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Premier Li Keqiang said in March that his cabinet planned to cut the corporate burden by about 1 trillion yuan (US$148.72 billion) in 2017, partly through changes to value-added tax and by slashing administrative fees.
Tang Dajie, secretary general of Beijing-based think tank the China Enterprise Institute, said the actual tax burden on mainland China was heavier than official numbers suggested. "These tax cuts aren't helping companies," Tang said. "It's just a few government surcharges and administrative fees that have been removed."
He added that companies may even end up paying more tax this year as the authorities were getting tough on collection.
The issue of whether Beijing is demanding too much tax from companies came under the spotlight at the end of 2016, when billionaire vehicle glass manufacturer Cao Dewang said production costs in China were higher than in the United States – mainly because of its tax regime.
The country's macro tax burden, the broadest measure, has reached nearly 40 per cent of its gross domestic product, a "deadly rate" for businesses, according to an earlier report by Chinese think tank the Unirule Institute of Economics.