Who decided to force us all to say CE rather than AD?

I happened to see this post at N.T.Wrong, decrying the introduction of CE etc, with which I entirely agree.  Conspiracies against the public are an evil thing; using them to evict Christianity from our society is pretty hateful.

No-one in the UK outside of these state-funded circles seems to use CE.

How much is a sestertius?

Someone recently asserted in my hearing that books were expensive in antiquity.  This led me to wonder how much they sold for.  A look in book 1 of Martial produced a price of 6-10 sesterces (ep. 66), and that 10 sesterces was the dole that a rich man might give his client (ep. 11).  That dole seems to have been daily (Juvenal, Sat. 1), and equivalent to 100 quadrans, translated ‘100 farthings’ by the Victorian translator. 

But how much is a sestertius? 400,000 sesterces was the minimum property requirement of a Roman Knight – the business class.  Somehow I feel that a sestertius cannot have been more than a dollar or two, unless the daily dole was enormous, and the minimum fortunes of a Knight likewise.  Does anyone have any thoughts on this?