Networking: How many emails did you guys send out to land an interview if non-target?

Current prospective midwestern SA who's sent out nearly 1100 emails out with a very small yield on referrals (Just 2). Was wondering how people increase their response rates to cold emails and how people conducted a call to get an non-alumni to refer you for a first-round. Seems like you would have to come across as a really spectacular candidate to get someone to refer you over someone from their perspective alma matter.