Normally, Scott Alexander writes very long posts. This one is very short and well worth reading.
His bottom line:
The correct way to report on this graph is "About twice as many economists believe a voucher system would improve education as believe that it wouldn't."
By leaving it at "only a third of economists support vouchers", the article strongly implies that there is an economic consensus against the policy. But its own source suggests that, of economists who have an opinion, a big majority are pro-voucher.
(note also that the options are only "vouchers will improve education" and "vouchers will not improve education", so that it's unclear from the data if any dissenting economists agree with the reporter's position that vouchers will make things worse. They might just think that things would stay the same.)
I think this is journalistic malpractice. I have no idea how Brian Williams can provoke a national scandal by saying that he was on a helicopter when in fact he was on a slightly different helicopter, but the Times will not get in trouble for reporting the opinion of the nation's economists to be the opposite of what it actually is, in an area with important policy implications.
Now, to be fair, this wasn't the New York Times. It was an op/ed by Susan Dynarski, a professor of education, public policy and economics at the University of Michigan. She has a Ph.D. in economics from MIT and is associated with the National Bureau of Economic Research, which, if anything, makes her statement even worse. She probably knows better. Still, Scott is right to criticize the Times because a good editor would have caught this.