DAN does an annual injury and fatality report. The typical yearly fatality count for recreational divers of Canadian and US residence is 90.
Dan report is available to members free of charge.
BSAC also does an
annual incident report..
Both the DAN and BSAC reports show a general downward trend in fatalities over the last decade.., except for last year in the UK where deaths spiked up to 25 rather than the typical 15-20.
As for your other questions about experience level / recent diving experience:
As in previous DAN reports, 40 percent of injured men and 50 percent of injured women had made fewer than 20 dives in the previous 12 months. About 25%/30% had less than 10 dives in previous 12 months.
Equivalent info for fatalities was a much smaller sample, but had the same sort of higher risk with <10 dives in the previous 12 months.
As for the cause of death, obviously it can be hard to determine and about 1/2 the deaths were "drowning". Air embolism and cardiovascular problems were tied as the next most common reasons, at 16 each out of 89 deaths in 2003.
Charlie