Adult acquisition of citizenship help

[Ro2 0]

A couple of years ago I found out I was born an American citizen because my grandparents became citizens in the 1950s and my mother automatically derived citizenship from them (Something she didn't know). Since she's been a citizen since then, I was born to an American citizen, therefore, I was born one myself as well as my brothers. We just finished the process of having my mother's citizenship recognized, and she now has her passport and certificate of citizenship. I am now in the provess of gathering up the paperwork I need to get my own citizenship recognized. According to the laws in effect when I was born (1978), one of the requirements for me to claim citizenship is that my mother must have lived in the US for at least 10 years, 5 of which must've been after her 14th birthday. She meets that requirement, as she moved to the US before her first birthday and left when she was about 20. My question, which is not at all clear in any of the documents about acquired citizenship I've read, is whether she must have lived those 10 years in the US AFTER she became an American citizen or does the time she spent as a resident count towards those 10 years? 
I really apologize for the lengthy post.

[NigeriaorBust 4,087]

  The current citizenship act counts all years that one is a legal resident in the US for the parents ability to pass along citizenship.  You would have to double check the actual words in the code for the version you are applying under,