Mirchandani's estimates of what the federal government spends on ink are on the high end:
A Government Services Administration study (6) had estimated the cost of ink (toner) to be 25.86% of the total cost of ownership of a printer (Footnote 2). Assuming this percentage, the estimated 2014 ink cost by the federal government is $467 million. A savings of 29.24% by switching to Garamond translates into an equivalent dollar amount of more than $136 million at the federal government level.Mirchandani notes that feds are projected to spend about $1.8 billion on printing in 2014. The GPO [Government Printing Office] accounts for a little more than a third of that ($680 million), but in 2013 it spent only $750,000 on ink. Even if that number could be zeroed out, a logical impossibility, the savings north of $100 million look pretty unlikely.
--David Graham, The Atlantic, on a sad piece of mythbusting