It is definitely gonna be an unsuccessful effort as no where would such an info e kept. Remember that decentralization is what we are talking about here thus, its never be possible. Don't forget as well that some folks got more than one Bitcoin wallet.
Is there a way to determine the number of people who are actually uksing Bitcoin till date? Who would have access to such information? Meaning a way to find out, how many new people have used Bitcoin in 2016 , so that we can say exponential growth is natural not artificially created by hoarders.