A flexible retirement plan, piloted in Shanghai, has proved unattractive to those of pensionable age and employers, according to experts.

Under the plan, launched in October 2010, people in technical and professional positions can decide to push back their retirement, while lower-skilled employees can also apply if they reach an agreement with their company, regardless of ownership or size.

That means men can extend their working life from 60 to 65, while women can continue working until their 60th birthday, instead of calling it quits at 55 for civil servants or 50 for ordinary workers in Shanghai, the "oldest" city in the country.