I think it depends, very much on how air defence is structured, and how much lead time it has.
There's a reason that command and control (and communications) aircraft are considered juicy targets (with additional options, intelligence, surveillance, reconnaissance), because they can see missile launches way over the horizon, calculate where it's going, and direct any air defence assets in it's path, and if multiple simultaneous launches, prioritize them.
The Israelis have Iron Dome, that is comparatively very expensive against rather cheap rockets.
Since actions occur in six second turns, though not in real time, you can calculate how many air defence assets you want to allocate to shoot down a missile, assuming you can detect and track it.
It tends to less one to one, than penetrating an air defence zone.
If you use spacecraft rules, fragmentation warhead takes out salvoes.