A recent analysis suggests wireless carriers should overhaul how they value their spectrum holdings.

The report from Deloitte said although rapidly rising demand for data in recent years prompted a sharp increase in the value of spectrum, companies continue to value it at its original purchase price — even if it was acquired years or decades ago.

The study said although spectrum licenses currently account for about 35 percent of U.S. carriers' assets, "the 'true' value of most WSPs' spectrum portfolios remains significantly understated."

The gap between how companies value spectrum and its actual value on the market, analysts added, would only climb as communications systems become more sophisticated and require more spectrum.

"Accurate valuation is no longer simply a matter of considering frequency and bandwidth in relation to coverage and data capacity," analysts wrote. "It increasingly depends on factors such as newly available frequencies, advances in technology, innovative ownership models and the advent of 5G networks."

The report said adjusting spectrum valuation processes would enable operators to properly assess their financial and operational capabilities, make better decisions about new technologies and optimize new spectrum purchases.

"Conversely, an undisciplined approach to spectrum management can hinder a company's performance and competitive prospects for years to come," analysts warned.

The analysis also said investors should re-think how they use spectrum to evaluate carriers — and noted that doing so could encourage more investment in wireless companies.

"A more accurate sense of spectrum value would enable investors to better value WSPs as a whole, while providing companies access to new financing opportunities based on spectrum assets that could significantly lower their overall capital costs," Deloitte analysts wrote.