Hitachi’s disk drive unit Wednesday is announcing another of the industry’s evolutionary steps: a new product with lower power consumption and other advances. But a study the Japanese company is releasing is more eye-opening, particularly about China.

The study, based on telephone surveys, focuses on user habits when it comes to digital media. It found that U.S. consumers, on average, store 907 digital songs, 924 photos, 25 movies and seven games.Those seem like substantial numbers and represent big jumps over the findings of a similar survey in 2005, Hitachi says.

More surprising is the fact that the disk drives of China - though the nation is sometimes called an “emerging” economy - seem to be even more packed.The average for consumers in that country is 1,311 songs, 3,083 photos, 24 movies and 22 games, the Hitachi study found. Young adults in China, age 18 to 24, have 3,195 songs on average, compared with about 2,065 songs for their U.S. counterparts.

“China is blowing away the U.S.,” says Larry Swezey, director of hard-drive marketing and strategy for Hitachi Global Storage Technologies.

The study attempts to derive a value for the stored content, whether it came from authorized download services, pirate sites, or users’ CDs and cameras. The average U.S. consumer now owns $1,660 worth of digital content, up 46% from 2005; half of the women who own digital devices described their data as either priceless or valuable, compared with 35% of men, the survey found.

Hitachi’s broader point is that the demand for disk drives and other data-storage media has become a truly global phenomenon. “We don’t understand how huge a force that really is,” Swezey says.

The company estimates the industry will ship about 550 million disk drives this year to meet the demand. All those spinning disks use a lot of power, particularly when they are waiting for a request to fetch data. Hitachi says its latest drive - which stores a terabyte of data on three disks rather than five - consumes 43% less power than its predecessor.