As part of its long term strategy to focus on and improve its most profitable properties, the Pennsylvania Real Estate Investment Trust is planning to sell off some of its underperforming and non-essential properties. The goal of the Philadelphia-based mall operator which owns the Exton Square Mall, is to earn up to an expected $225 million by the end of the first half of next year, writes philly.com.

The properties that are up for new ownership include two Center City retail buildings as well as four shopping malls in Pennsylvania, Alabama, and Virginia that have been significantly underperforming.

The goal of the sale proceeds is to attract a higher level of tenants and to peak greater investor interest by improving the square foot sales revenue of its remaining properties, a key measure of success for malls. As a result, the funds will be focused on properties with prime locations in wealthy areas that have additional competitive advantages.

“We have a phrase here which is called addition through subtraction,” said Chief Executive, Joseph Coradino. “You’re not selling assets to sell assets. You sell assets to drive the quality of your portfolio.”

The selling spree, now in its third year, has already generated close to $500 million for PREIT and Coradino pointed out that the funds generated from previous sales have already been invested in other major projects. These include $325 million for the Gallery at Market East renovation that PREIT is working on with partner Macerich Co. as well as the major improvements being made on the Plymouth Meeting Mall which has already signed the area’s first Legoland Discovery Center as a tenant.

The sell-off of the malls that are not performing that well has also raised PREIT’s average yearly sales per square foot to $428, which is $44 higher than a year ago, a fact that is boosting its position in both the eyes of investors and potential tenants.

“How do you get any of these high-end tenants? It’s by having a high-end portfolio,” Coradino said. “You get a much more compelling relationship with retailers.”