The city's local newspaper Shanghai Morning Post said that people riding for free are ripping off the metro system about 10 million yuan a year. An estimated 0.16 percent of the city's daily 6 million metro riders never pay for their tickets.
But the percentage of freeloaders in Shanghai's big metro stations reaches 2 to 3 percent, said the newspaper.
"It's hard to estimate the percentage of riders taking free rides because it varies from station to station and from time to time," said Lan, without offering a figure.
The person who recorded the popular short video, who identified himself only as Chen, said more than 1 million people watched his footage since he uploaded it to youku.com on Monday.
"And 21 ticket evaders in 96 seconds is not the highest. I saw more than 30 people do it within one minute during the evening peak period," said Chen.
The video recording, which shows that most of the freeloaders seem to be migrant laborers, also triggered heated discussion about whether migrant laborers are more likely to be ticket evaders.
However, Wu Yizhong, a 28-year-old white-collar worker from Shanghai, said she rode the metro free when she lost her ticket once. "I saw many people do it, including white-collar workers and local students who were speaking Shanghainese. I don't think it's only migrant workers," she said.
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