It is a remarkable achievement, yet for a government fixated on stability such figures are also a cause for concern. The economy, despite its robust growth, does not generate enough good professional jobs to absorb the influx of highly educated young adults. And many of them bear the inflated expectations of their parents, who emptied their bank accounts to buy them the good life that a higher education is presumed to guarantee.

“College essentially provided them with nothing,” said Zhang Ming, a political scientist and vocal critic of China’s education system. “For many young graduates, it’s all about survival. If there was ever an economic crisis, they could be a source of instability.”

In a kind of cruel reversal, China’s old migrant class — uneducated villagers who flocked to factory towns to make goods for export — are now in high demand, with spot labor shortages and tighter government oversight driving up blue-collar wages.

But the supply of those trained in accounting, finance and computer programming now seems limitless, and their value has plunged. Between 2003 and 2009, the average starting salary for migrant laborers grew by nearly 80 percent; during the same period, starting pay for college graduates stayed the same, although their wages actually decreased if inflation is taken into account.

Chinese sociologists have come up with a new term for educated young people who move in search of work like Ms. Liu: the ant tribe. It is a reference to their immense numbers — at least 100,000 in Beijing alone — and to the fact that they often settle into crowded neighborhoods, toiling for wages that would give even low-paid factory workers pause.