Bryce:
The price per ounce has spiked from $4.37 in 2001 to $7.32 in 2006, so over a short period of time yes, it has risen.
However, if you look between 1978 and 1982, you'll see a spike to $22 in 1980; this spike was, however, pre- and pro-ceeded by values slightly above $10.
There isn't any comparison to the value of the dollar, however, so I can't factor that into silver values over time.