Court will deliver written opinions in roughly 170 cases per year...
Not nearly that many--more like less than half of 170 according to the following:
The number of slip opinions published each Term has varied over the years from as few as 75 to as many as 150.
The number of cases handled by the Court -- with full opinions -- has been reduced substantially in recent decades, from some 140-150 to 70-90.
80 opinions this past term.
You're right. It will deliver summary judgement in about 120 cases, written opinions in about 80-90.