The only reason 2015/16 was a deficit was the LPC were in power for the last 3 month of that fiscal year and they instructed every department to spend everything they had.

In March 2014/15 (the last full year Harper held the federal purse strings) the feds spent 3 Billion in deficit that month. In 2015/16 when the Liberals were in charge of the finances for the last quarter of that fiscal year March 2015/16 spending was in deficit by 10.4 Billion. That is a difference of 7.4 BILLION even though the government received a full 1 billion more revenue than the previous year.