Where do i find the statistical rate in countries like nigeria and nepal?

a href="http://www.un.org" rel="nofollow"http://www.un.org/a would be a good place to start. I will warn you though it takes a lot of searching to find the reports you are looking for. But, this is the official United Nations site and I frequently use it for research. They do have an enormous amount of information like this on there, but most people give up after 30 minutes of searching the site. You just have to keep using different keywords. Good luck.