Lines from a novel: "I wish I ..."

[Tom]

Hi

Please see below:

"It's about time you kicked that habit, Bart," he said.What do you do with all your money?"

"That is a good question. I wish I knew. It comes and it vinishes, and I have damn all to show for it."

Could you please explain the highlighted line to me?

Tom

[Alan]

Hi Tom,

You quoted:

[Tom]

Thanks, Alan.

So, may I assume?

Damn all= nothing at all(in the given context)

If OK, then please send me a yes

Yours

Tom