I am not sure older people have sex quickly after dating, since older people tend to be more conservative and also have less sex in general. So its probably more important that rather than following a number you do what feels right for the both of you.
You say that you want to make sure that care is safe before test driving it. If you are worried about STDs, then you can have a serious conversation about STDs before having sex, or you can ask that both of you take an STD test, but please make that suggestion very carefully. Keep in mind that STD rates are much much lower for older people than younger people.
If you mean that you want to make sure this is a good relationship before you will have sex, then a general rule you can follow is that you will have sex when you decide to commit to this relationship. You can have it before though, because sex with someone you later turn down isn't a disaster. I don't know if its a good idea to have sex just to lock down the guy when you don't actually want to. You should at least like the guy and at least kind of want to try it out.
I will warn you that the longer you delay sex, the more men you will turn off, and many of these men will actually make great husbands. And if you are waiting a year, then unless there is a really good reason, most of the best men will leave. If you just aren't into sex with them, then you might want to look into personal issues that is causing your lack of interest, medical issues, or maybe he isn't the one.
And of course, you can't be too sure you will be sexually and personally compatible with someone until you are living with them and having sex. Pre-sex dating is meant to eliminate people who are obviously not compatible, and living and having sex with a boyfriend eliminates harder to detect incompatibilities.