maybe a statistical expert could help me out.

I am interested in an event, that occurs in mean 30 times per month with an SD of 10. This relies on a data collected over a period of 1 year.

Now I want to compare if this event happens as often after the coronavirus pandemic.

So i have got 12 months of data compared to the 1 month now.

Which statistical test could i perform?

Thank you in advance.