I see a figure computed for "how much of total wages earned while living or working in New Jersey". How was this computed? I also lived in MA for part of the year.

You will need to look at your w2 and your entries for allocations. You also want to look at the worksheets associated with determining the income in your return. Each state has their own method of calculating.

 To print or view  your forms, including all worksheets:

• In desktop, switch to Forms Mode. 
• For online:
  1. On the left side, select  Tax Tools
  2. Select Print center
  3. Select Print, save or preview this year's return
  4. If you have not paid, select pay now.