Obtaining P values for 2 variables

Im having some trouble solving this question..
I have 2 populations in which I have calculated the risck per patient-year for an specific event, in 2018 and 2019.
Now I have:
Event per patient-year:
Population 1
- 0.48 in 2018
- 0.32 in 2019
Population 2
- 0.61 in 2018
- 0.53 in 2019
What im trying to find is a way of proving that population 1 has a significant lower risk of events per patient-year than pop 2 (in each year and both years)
Is there a way of converting this into a p value?
Already tried t-test and Wilcoxon with no success, since I do not have a grouping variable…
Thanks in advance and sorry for some grammar errors and other simple stat mistakes.
Do you have the sample size for the each of the four groups?

Can you think of 0.48 as a proportion? A proportion of events.

Then you can run logistic regression with time and group as explanatory variables.