My husband received 1st SSA-1099 in 2017. Has lump sum payments for 2014-16, inputting info where do I find tax exempt interest on prior forms

[campfirenow]

When I input the lump sum amounts in regards to the SSA-1099 it is now asking I get the AGI, tax exempt interest and taxable SS benefits for each of those years.  I can find the AGI and the taxable SS benefits reported would be zero, but do not understand where I find the tax exempt interest amount

[Anita01]

Line 8b of the 1040 shows tax-exempt interest