I've never seen accident figures for the SHar, but the US AV-8B's certainly don't help the 'Harrier' overall stats.
I can't remember if it was here on PPRuNe or in some other media, but the inimitable John Farley wrote a superb article about the initial US attrition rate with the AV8A.
Am on dial-up today so I would be retired before I could find it but perhaps a PP search by someone who could post a link would set the record straight.