If you're wondering why Ron Paul didn't vote, he didn't have a chance because the vote was abruptly moved up a day in advance and rushed through while he was campaigning in Texas.
In Congress, a "not present" is the same as a "nay" vote since only the "yeas" count. Given Paul votes against most legislation, 92% sounds about right.
Aren't they recorded differently though? Even though it doesn't change the results, you should be able to tell the difference between those who vote "nay" and those who just don't vote.
http://www.techdirt.com/articles/20120426/14505718671/insani...