Somebody failed math: http://www.msn.com/en-us/news/politics/president-trumps-budget-includes-a-dollar2-trillion-math-mistake/ar-BBBsx5q?li=BBmkt5R&ocid=spartandhp
"President Trump’s budget includes simple accounting error that adds up to a $2 trillion oversight. Under the proposed budget released Tuesday, the Trump Administration’s proposed tax cuts would boost economic growth enough to pay for $1.3 trillion in spending by 2027. But the tax cuts are also supposed to be revenue-neutral, meaning that trillion dollars is already supposed to pay for the money lost from the tax cuts. Former Treasury Secretary Lawrence Summers called the oversight an "elementary double count" and "a logical error of the kind that would justify failing a student in an introductory economics course" in an op-ed in the Washington Post."