Asphalt and Concrete Manufacturing

I am modeling the impacts of a new asphalt and concrete manufacturing facility.  The facility will, at full production, produce per year:

• 300,000 tons of asphalt
• 200,000 cubic yards of concrete
• 200,000 tons of recycled concrete and asphalt
• Enough imported material to sell 200,000 tons of raw aggregate.

The anticipated volume of aggregate sales is 200,000 tons per year.

Should I use "Industry Output" - defining value by (1) total sales revenue or (2) sales plus a change in inventory?  If sales plus change in inventory - how do I quantify the change in inventory and what is the purpose of quantifying inventory changes?

Thank you,