That is 1 CE = 1 AD, and 2016 CE = 2016 AD. The word common simply means that it is based on the most frequently used calendar system: the Gregorian Calendar. Both measure the number of years before the approximate birthday of Yeshua/Jesus. Designation of a particular year in BC and BCE also have identical values.
Francium is a chemical element with symbol Fr and atomic number 87. It was formerly known as eka-caesium and actinium K. It is the second-least electronegative element, behind only caesium. Francium is a highly radioactive metal that decays into astatine, radium, and radon. As an alkali metal, it has one valence electron. Bulk francium has never been viewed.
The good news is that you will never see enough francium in one place to cause a problem. At any given time, less than an ounce of this wildly reactive element exists anywhere on the whole planet. Francium is so volatile that it has a half-life of only about twenty minutes!