But forecasting is more murky art than exact science and a target missed by $10 billion or so isn't unusual. The 2013-14 deficit number, in fact, has bobbed up and down over three consecutive budgets.
The 2012 budget predicted a shortfall of $10.2 billion for 2013-14.
The 2013 budget upped that prediction to $18.7 billion.
The 2014 budget dropped it to $16.6 billion.
In similar fashion, the deficit for 2012-13, was forecast to be $21.1 billion in the 2012 budget.
By the next year, it was up to $25.9 billion. In fact, the actual deficit for 2012-13 was $18.9 billion.