In the past year I lost 20 kilos or In the past year I've lost 20 kilos

[paokricc]

Should I say/write, "In the past year I lost 20 kilos" or "In the past year I've lost 20 kilos"?

If both are possible, do they mean the same thing?

If so, which would you use or do you prefer?

Thank you.

[Firefox]

In the past year I've lost 20 kilos.

But I think that In the past year I lost 20 kilos may be quite current in American English.