Investment income for purposes of earned income credit are:
income, not loss, amounts from Form 1040 lines 2a, 2b, 3b and 7
That would be:
tax exempt interest,
taxable interest,
ordinary dividends
and capital gains
Form 8814 line 1b
Royalties and rental income
passive activity net income
There is also a worksheet in IRS publication 596, Worksheet 1
IRS Publication 596
