williamsnathan
What are you trying to achieve?
On the basis of your post, I assume you have found the HSE spreadsheet which looks at rates by sector.
But these are rates for REPORTED incidents not an estimate for REPORTABLE incidents.
I don't think HSE has yet published any research into REPORTING rates since RIDDOR 2013 came into force.
However previous research indicated that underreporting (across all sectors) was about 50% in terms of reportable accidents sustained by employees and over 90% for the self-employed.
Reporting of REPORTABLE accidents to the self-employed should have improved with the changes in RIDDOR 2013, but the picture for employees is not clear and will have been muddled in terms of attempting to compare like with like by changing the threshold for reporting of Over N day accidents from N = 3 to N = 7.
However, of course, levels of underreporting are not consistent across the board. Some organisations will have virtually no underreporting, others will never report until forced to!
So, suppose you work for a medium sized contractor, who reports everything they should - if your accident rate is twice the rate given on the HSE stats, then statistically you are probably no worse and no better than the average for the sector - due to how much underreporting you should be estimating for.
But comparing against the average is not much help in assessing your performance, as you are looking at a vast sector with diverse activities, some of which are inherently more dangerous than what your organisation probably does - UNLESS your operatives do the high risk tasks such as demolition, steel erection etc etc.- tasks which most Contractors choose to sub out.
Then you need to know whether you are benchmarking against companies with similar strategies for collation of data.
You might decide to keep integrated statistics that include for the supply chain, so as to include those demolition workers, steel erectors etc etc, or you might stick to only your direct workforce. BOTH are entirely valid approaches from a statistical standpoint.
There are so many variables to take into account, that benchmarking is actually VERY difficult, as has been discussed on numerous threads on these Forums.