Why doesn't form 1040 line 5a get filled in from the data I entered in from my 1099-Rs for my pension and annuity?

I have 3 1099-R forms. One is for an IRA, one for a pension, and one for an annuity distribution. I at least expected the amounts from the pension and annuity to flow into line 5a as well as 5b, but there is nothing on line 5a.