When comparing this year and next year for W-4 in Other Tax Situations, what is the source for the Other Income and Losses for 2018?

[emconfused]

I don't recognize the amount displayed for 2018. 

[MichaelL1]

Look over the Form 1040 and the schedules, and where the other income and losses are will refer the Schedules it is coming from.

Most likely it is on Sch 1 and then it will say Capital Gain or Sch C, Sch E, then go to that schedule and look at it.