When you converted your entire balance in traditional IRAs to Roth leaving nothing in your traditional IRAs at the end of 2010, your entire basis in nondeductible traditional IRAs was distributed from your traditional IRAs. Unless you subsequently new nondeductible traditional IRA contributions or rolled over to a traditional IRA after-tax money from a qualified retirement plan like a 401(k), you no longer have any basis in nondeductible traditional IRA contributions.
