*In Google Sheets there is now the Alternating rows formatting. It's almost the equivalent of of tables in Excel.*

**Background**

What if I have a sheet that is **sorted by Invoice #'s**, my unique number associated with a bill I send out to someone, but that someone breaks my invoices up into multiple line items associated with their own number called a Purchase-Order-Number.

**Question**

How do I Highlight every other invoice such that I can more easily distinguish which Purchase-Orders belong to which Invoices?