Are all new computers 64-bit?

Excuse me, but could you please clarify for me if all newly manufactured computers today are exclusively 64-bit systems? I've been hearing a lot about the advantages of 64-bit processing, but I'm not entirely sure if this has become the industry standard across the board for all new computers that are being released. Would it be accurate to assume that every new computer on the market today operates with a 64-bit architecture, or are there still some exceptions to this rule?