I wasn't talking about the success rate for any individual drone, but about the cumulative effect. And the success rate of individual missions depends very strongly on which part of the front you are looking at and what kind of missions are flown.

Just to give you one figure: estimates are that between 1000 and 1500 Shaheds have been downed by interceptors during last February. That's not a 100% kill rate but it definitely isn't 1% either. And they're getting better every week.