The GAO estimates savings of over $4B over 30 years if the dollar bill is eliminated and dollar coins are used instead.
Two 1990 GAO report said this: Australia, Canada, Japan, and the major Western European countries all now use a coin for monetary transactions at, and in many cases well
above, the level for .which Americans use the paper dollar. The United States introduced the Susan B. Anthony l-dollar coin in 1979, but it was not accepted by the public.
Now we have Sacagawea and Presidential dollar coins. It has been postulated that the public didn't like the Anthony dollars because they were too similar to 'quarters.' The Sacagawea and Presidential dollars are sufficiently different and would be less likely to be mistaken for quarters.