Economists are generally willing to accept most of Treasury's forecasts in this month's federal budget although they repeatedly question its prediction for wages.
Treasury boss John Fraser will get the opportunity to defend his department's forecasting when he faces senators on Tuesday and when parliament resumes after Monday's holiday in Canberra for Reconciliation Day.
Treasury forecasts wage growth of 2.75 per cent in the next financial year, rising to 3.25 per cent in 2019/20 and 3.5 per cent thereafter.
The latest wage price index - Treasury and Reserve Bank's preferred measure of wages growth and released the week after the budget - did little to comfort economists' concerns that the Treasury is being overly optimistic.
The annual rate remained at 2.1 per cent as of March, only just above a two-decade low.
Treasury figures released over the weekend claiming the Turnbull government's personal income tax cut plan is aimed at middle-income earners predict the average wage will be $120,000 in a decade's time compared with $84,600 now.
This is also based on wages growth of 3.5 per cent year after year from 2020/21 until 2028/29.
Labor senators will be looking for more detail on the seven-year personal income tax plan that featured in the budget during the Senate estimates hearing.
While economists think Treasury is being optimistic on the wages outlook, it is being somewhat more conservative in its view on the overall economic outlook when compared with the Reserve Bank and other institutions like the International Monetary Fund.
It expects growth to be three per cent from 2018/19 whereas the central bank is looking at a rate of 3.25 per cent.
In the interim, growth could be on target for Treasury's 2.75 per cent prediction for this financial year.
At this stage, economists are forecasting the economy grew by around 0.8 per cent in the first three months of this year when the national accounts are released on June 6, double the pace seen in the December quarter.
This would see the annual rate rebound to 2.7 per cent from 2.4 per cent previously.
Economists will update their predictions when business investment figures are released on Thursday and data for company profits, inventories, international trade and government spending are issued next week.
