They give the excess events for vaccinated individuals compared to those not vaccinated, per 100,000 vaccinations. For males age 16 to 24, the excess per 100,000 vaccinations is 5.55 for Pfizer and 18.39 for Moderna. These numbers might be useful if you were comparing the badness of these events with the goodness of whatever you think is the number of Covid infections prevented per 100,000 vaccinations (which obviously depends on the general prevalence of Covid).

They also give a ratio, which could also be interesting, and which you can't deduce from the excess events without knowing the number of events in the reference group.