[Vocabulary] But no proof that...

[Habituellement]

Hello.

Please could you tell me if the part in bold below is correct English?

At first sight, a million newly published books per year seems to be an extremely surprising figure but, after further consideration, it does not seem particularly overwhelming, given the billions of potential book writers who inhabit our planet. There is a high probability but no proof that the number of published books has fallen since 2000.

Thank you very much for your answers.

 

[GoesStation]

Or dashes.

 

[probus]

While setting off the phrase with commas or dashes would improve readability and clarity, I think the passage without them cannot be called incorrect. It's fine as written.

 

[Rover_KE]

Habituellement, please tell us the source and author of any text you quote.

 

[Charlie Bernstein]

While setting off the phrase with commas or dashes would improve readability and clarity, I think the passage without them cannot be called incorrect. It's fine as written.

Yup. Commas wouldn't actually add anything. It's understandable and reads easily either way.