Round and round and round it goes, where it stops, nobody knows.

That expression about sums up the clearest indication Walmart has when it comes to guessing how much its worldwide corruption investigation will cost related to violations of the Foreign Corrupt Practices Act.

Walmart disclosed in its latest Form 10-K filing last week that, so far, it has shelled out a whopping $439 million in total costs for fiscal years 2013 and 2014 for compliance enhancements and investigation costs related to possible violations of the FCPA. Broken down, these costs amounted to $282 million in fiscal year 2014, in addition to the $157 million spent in fiscal year 2013.

As Compliance Week previously reported, the investigation resulted from allegations that executives at Walmart's Mexico unit bribed Mexican officials to smooth the way to open stores in prime locations. The scandal came to light in a Pulitzer Prize-winning report by the New York Times in 2012.

According to Walmart's Form 10-K filing, dated March 21, Walmart said it expects to continue to incur costs “incremental to the $282 million of costs incurred in fiscal 2014 in conducting our ongoing review and investigations, and in responding to requests for information or subpoenas seeking documents, testimony and other information in connection with the government investigations, and in defending the existing and any additional shareholder lawsuits and any governmental proceedings that are instituted against us or any of our current or former officers.”

In a recent earnings statement, Walmart Chief Financial Officer Charles Holley said, “We anticipate expenses for FCPA matters and compliance-related enhancements to range between $200 and $240 million for fiscal 2015.”

In a Feb. 20, 2014, earnings call, Holley said Walmart spent $58 million on FCPA and compliance-related expenses, for the quarter—below its forecast of $75 to $80 million. He added that $38 million of these expenses represented costs incurred for the ongoing inquiries and investigations, while the remaining $20 million related to its global compliance program and organizational enhancements.

“Our process of assessing and responding to the governmental investigations and the shareholder lawsuits continues,” Walmart stated in its latest Form 10-K filing. “While we believe that it is probable that we will incur a loss from these matters, given the ongoing nature and complexity of the review, inquiries, and investigations, we cannot reasonably estimate any loss or range of loss that may arise from these matters.”