You shouldn't rely on KSI or the KSI adjusted. Look at SI and K independently. SI is incompatible with K as data set. If K goes up 50% and SI goes down 10% every cheers when in fact it would be terrible. SI data is also very unreliable as it often doesn't get reported. a Serious Injury is not as it seems. It can be something quite minor most of the time.
Despite massive technological improvements, the rise of speed cameras and slashing of speed limits everywhere road casualty statistics have not changed for over a decade.
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