Use parentheses to enclose words or figures that clarify or for an aside. Commas could have been used in the above example.
Parentheses show less emphasis or importance.
Dashes could also have been used instead of parentheses to show emphasis. Use parentheses to enclose numbers of listed items in a sentence. Periods or half parentheses are acceptable also. Periods go inside parentheses only if an entire sentence is inside the parentheses. OR Please read the analysis.