The ratios are unlikely to change, though the absolute numbers probably do. Given the increases in both population and gun ownership, the most likely change is an increase in incidents.
20 years ago we didn’t have the number of illegal aliens coming into the US as we have in the past 10-15 years, which included a lot of active and future criminals, esp. from the drug cartels and gangs.
The figures for gun use for protection should be at least double that of the studies.