I am having a strange problem in Swift `NSDateFormatter` with a certain date,

here is my code:

```
let stringDate = "25/03/2015"

let dateFormatter = NSDateFormatter()

dateFormatter.dateFormat = "dd/MM/yyyy"

let date = dateFormatter.dateFromString(stringDate)

```

This code is working fine and I'm able to get the date from the string. However, if I change the date to "25/03/2016" or "31/03/2017" I'm always getting `nil`.

This is very strange, has anyone also had this problem? Anybody knows what could be the reason behind this strange error?