"I've honestly never understood why it's such a big deal. Your past is in your past. It's the present that's important, right?"
"There is no proper way to answer this but in my experience, a mature woman / man should not need to worry about it. Seriously, what does knowing the answer do to help the relationship? It doesn't. Usually I would disagree with the statement "Ignorance is bliss" but in this case... it is. Don't ask, don't care. Enjoy the person for who they are now..."
"I always refuse to answer that question because no matter what the number is, it is going to cause problems. I feel like insecure/jealous individuals opt to ask that question. If the girl is clean and genuine, and not a shit head then why would I care how many guys she's slept with?"
"Respect yourself enough to realize that they're with YOU because they want to be with you. The "am I just another number" line of thinking is usually a self-fulfilling prophecy."
"In the past I've always lied. I cut my number in half. Then I gave my real number. Then I realized it shouldn't matter. Nothing good ever comes out of asking that, and it's in the past so it shouldn't matter."
The general consensus seems to be that a person's history means nothing. If sexual history is so shameless, then why not share it with your partner? By stating "it doesn't matter," that shows how everyone you've been with... well, doesn't matter. You're flat-out stating how other human beings in your past aren't worth mentioning nonchalantly. That's the only self-fulfilling prophecy I see: each present second becomes the past, so if the past doesn't matter, nothing does.
Having said that, I'd rather be with someone who had 100 partners that doesn't treat youth like crap or blindly follow authority, than a virgin who's a complete drone. In today's society, it seems like most relationships end whether they're between monogamous or promiscuous people. Still, if a person has had few partners, male or female, they're likely looking for someone who also isn't promiscuous. Have some courtesy to let others know exactly who they're getting into a relationship with. If you think your date dislikes promiscuous individuals, then let them know you're one when they ask and don't waste each other's time.
An analogy would be me asking what someone had for lunch today. They'd tell me because it doesn't matter, right? If sex is also arbitrary, then casually reply, "oh, I've been with about 50 people." Some people are simply curious about one another because it's like asking if they've ever gone mountain climbing. They want to know what experiences their partner has lived, even if they're of the sexual variety. If one cannot expect an answer about sex, then we might as well not wonder what foods a partner has tasted, or how many countries they've been to, and so on. After all, the message is that sex is just something people do, like tasting foreign cuisine or traveling the world.
Open communication is often cited as a key ingredient in any romantic relationship, so why be secretive if sex is trivial? If someone loves you, they won't leave. If you love them, you'd answer truthfully. What backwards world would consider hiding your past a secure and confident trait? This one, apparently.
I'll also leave this link even though I'm the first to question every scientific study: Premarital Sex, Premarital Cohabitation, and the Risk of Subsequent Marital Dissolution. I know correlation does not equal causation. Basically, being promiscuous does not cause divorce. However, there is a correlation between failed marriages and promiscuity. Many citizens have seen these studies, so if someone is concerned over this issue, here's why. It's not because they're inherently insecure, it's because society has conditioned them to always take science and numbers seriously.
So to sum this up, lying or keeping secrets from a partner is a sign of invalidation and not mature in my book. If partner count doesn't matter, then answer nonchalantly but honestly, lest you're the coward.