Yeah, the efficacy rate basically is how well it works you know to make it quite simple, and the different vaccines. I tried to explain earlier that it is, of course, dependent on the vaccine, but it's also dependent on the situation, where you test the vaccine. So if you take a vaccine in the clinical trial and you take it in an environment in which there's a very high load of virus so this example of the clinical trial in Brazil, among healthcare workers during a tremendous epidemic in, In Brazil, so they were exposed to loads of doses, loads of virus, every day, and then the protection then was 50% in other words, 50% of them still were not necessarily getting sick, but they became positive, because they were exposed to the virus. So in that situation that's the most difficult situation in which you can test the virus, and test the vaccine. And then the result may like like that, if you test in a population where very few people are sick, you will find also that the protection is much higher, because the people are not exposed to the vaccinated people are not exposed to so much and not to such high doses of drivers. So that is one reason why in the clinical trials, there are some differences so for instance this difference between 50% in Brazil 80% protection was the same, same vaccine in Turkey. It all had to do with how much exposure, the vaccinated people have. So that's, that's one thing. The other thing that's very, very important concept is that there's a difference between what you see in a clinical trial, and real life experience, and real life experience actually is the most important thing. And so to still take the same cinovec vaccine in a small town in Brazil, near Sao Paulo, and a small town named Serrana. They've done an experiment, one can call it so they vaccinated, all adults in this town of 46,000 people with the Sinovac vaccine and what it showed was that the protection, not just for the people that had been vaccinated, but for the whole population, so including the children that have not been vaccinated, was 95%. So they have achieved herd immunity. And when you have herd immunity. That's the idea of herd immunity, you're not only protecting yourself, but you're also protecting others. So, a vaccine. And this was in the period in which the number of infections in Brazil were very high so in Sao Paolo, things went very bad. Whereas in Serrana, where they had been vaccinated, they were protected. So this real life efficacy, showing that when sufficient people are vaccinated. This protection for the vaccinated, but also for the people that are not are not yet vaccinated, so in that case children, for instance.