Soaring housing prices and a lack of new apartments could lead to a sizeable hike in asking rents by year-end, according to a study released today by the USC Lusk Center for Real Estate.

The Casden Real Estate Economics Forecast predicts occupancy levels will continue to improve at a steady pace with average rent increases ranging from 3.5 percent to 6 percent this year.

“The new supply of apartments has not kept up with demand from newcomers attracted to jobs in our diverse economy and the Southern California Lifestyle,” said Delores Conway, director of the Casden forecast, in a prepared statement.

The study found the average rental rate for a two bedroom apartment should rise to about $1,500 in Los Angeles County.

In L.A. County, the average one-bedroom apartment is expected to cost $1,200, a two-bedroom unit $1,500 and a three-bedroom $1,700, according to the report.

But that figure varies widely from one location to another.

While the average West L.A. two-bedroom unit was fetching $2,319 in rent, the average two-bedroom unit in the Antelope Valley was half as much.

Even though low interest rates made many renters jump into homeownership, Los Angeles apartment landlords haven’t suffered, as occupancy levels have remained historically high.

According to the report, rents have increased 15 percent from 2001 to 2004, as the Los Angeles region’s economy has continued to pick up steam and add new jobs.

Still, steep land prices and a dearth of developable land is keeping new apartment buildings from getting built and easing housing pressures, the report said.

There are roughly 1 million apartment units in Los Angeles County, which has grown by 1 percent a year for the last five years, the USC economists found.