Note that the ratio, or price of silver, in terms of US dollars in existence, is indeed at its all-time 100-year low.
In 1980, the all-time high was 0.361, whereas the ratio is currently at around 0.004. The US monetary base is currently around 3 946 billion dollars (or 3.946 trillion). Therefore, if silver was today at its 1980 value, relative to the monetary base, it would be around $1 424 (3946*0.361).
So, in terms of US dollars in existence, silver is trading at 1.19% (17/1424) of its 1980 high – it is the bargain of the century.