Sorry, that's heresy....
When "One died (Christ) all died"! Christ's death was a corporate death. It included all mankind. Accepting this truth by faith didn't make it so...it merely made it effective in your life.
Read Eph chapter 2:
"God, who is rich in mercy, 5 made us alive with Christ even when we were dead in transgressions--it is by grace you have been saved.
When we were dead in sin God made us alive in Christ. Hence grace saved you 2000 years ago. Nothing about faith here....
6 And God raised us up with Christ and seated us with him in the heavenly realms in Christ Jesus, 7 in order that in the coming ages he might show the incomparable riches of his grace, expressed in his kindness to us in Christ Jesus.
According to this God raised "us" (the human race) up in Christ Jesus and took this glorified life to heaven so that in the coming ages, when you came on the scene, you might see the love of God in Christ Jesus.
8 For it is by grace you have been saved, through faith--and this not from yourselves, it is the gift of God-- 9 not by works, so that no one can boast.
So you were saved by grace 2000 years ago in Christ. When as an individual you came along you accepted this truth by faith. Accepting didn't make it so, for it already was. It simply made it effective in your life. And this salvation can not be earned by your righteousness.