A newly released federal report estimates the problem-plagued Phoenix payroll system has already cost government coffers more than $1 billion and could require an additional $500 million a year until it is fixed.
The majority of future spending is being described as ``unplanned'' costs and doesn't include more than $120 million in expected one-time expenses.
The report, being made public this morning, says the government's best estimate is that it could take five years to stabilize the Phoenix pay system.
Since it launched, Phoenix has resulted in countless public servants overpaid, underpaid or not paid at all.
Auditor general Michael Ferguson lambasted the system last month in a report that called Phoenix an ``incomprehensible failure'' of project management and oversight, which led to green-lighting a system that wasn't ready.
Privy Council Clerk Michael Wernick fired back at Ferguson during a Commons committee hearing this month, accusing the auditor of making ``sweeping generalizations'' about public servants.