Thanks, MDinana - hope you can find more on that.
Good catch, Teslinhiker - I'm glad you found that one.

I expect that cell phones, VHF/ham radios and EPIRB/PLBs are saving more people these days.

I found this scorecard for EPIRB/PLBs:

In the United States, in 2009, for PLBs alone:
33 people rescued in 26 incidents.
The total for the US in 2009, when EPIRBs are added:
195 people rescued in 94 incidents.
A signal mirror should backup a radio distress signal, like a 406 MHz PLB (ACR PLB) (Ocean Signal PLB)