Does the US CBP have other methods of tracking entries & exits from US other than i-94w?

Question

Worried traveller - please help!

Went to the US in 1993 from the UK, but can't remember if i handed my 1-94w in on my departure. When I return, would they know when I left the US, and there would be no problem re-entering?

Answer 1

The computer lists I-94s.  Everyone knows these are imperfect, so they might shrug it off, but if there is a problem, your plane ticket or airline passenger record which you can get from the airline should suffice as proof.