Why are tax revenues slowing? The CBO really didn't have an answer, as it projected that revenues from "individual income taxes are expected to fall by 0.2 percentage points of GDP."
Often something like that would be an indicator of a lack of economic growth, but some have argued this may be related to more wealthy taxpayers not making large estimated tax payments, hoping that major tax cuts are approved this year by the Congress. There is no hard evidence to back up that assertion.
As for the level of the deficit, $693 billion would be a big jump from the $585 billion deficit in 2016 - a 23% increase.
Here is what the federal deficit has done in the last 10 years:
2007 - $161 billion
2008 - $459 billion
2009 - $1.413 trillion
2010 - $1.294 trillion
2011 - $1.300 trillion
2012 - $1.087 trillion
2013 - $679 billion
2014 - $485 billion
2015 - $438 billion
2016 - $585 billion
Like 2016, the 2017 deficit seems to be going in the wrong direction.
The 2007 deficit under President George W. Bush was the lowest deficit since the budget was balanced for several years during the Clinton Administration, in the late 1990's.