release.gpg changes each time it is generated

[abdelkader belahcene <abelahcene@gmail.com>]

HI,
Is it normal that each time I generate  file release.gpg, I get a new one.
here are 2 samples  for the same Release
 diff Release.gpg Release1.gpg
4,6c4,6
< iEYEABECAAYFAkq8ifgACgkQ7fxInIbeDykBhQCdHxjAimaLH1CpXYh9FC+AQEHs
< 06wAn1V5RAglR6/dBtPDW4QF5XV1GLgI
< =2uMA
---
> iEYEABECAAYFAkq8jF8ACgkQ7fxInIbeDyl4qwCgigkQgDNCtY03c4FdlLaD+4do
> 2I0AoIWYjPbkUzXNlHEUjcYqqgNEiKKt
> =NAhJ

In this case how it can check the thrust of the file ?

Thanks for help