From the graph, most accidents happen on the single carriageway where a total of 217,192 of accidents have been recorded. Most accidents happened on single carriageway roads where the speed limit was 30mph with the total recordings of 134, 459; this could indicate that most accidents happen in populous areas where the speed limit is low depending on how busy that area is and how much traffic there is. Drivers might be exceeding that limit while overtaking causing hazards and causing accidents happening. The second most number of accidents with 40,683 in total happened where the speed limit was 60mph. This might be caused because of the excessive speed when driving. As stated on https://ec.europa.eu/transport/road_safety/specialist/knowledge/speed/speed_is_a_central_issue_in_road_safety/speed_and_accident_risk_en the higher the speed of the vehicle the more risk of an accident happening.
Dual carriageway recorded 60,797 accidents. Most of the accidents happened where the speed limit was 70mph with total accident recordings of 26,143. The second area where most of the accidents happened is where the speed limit was 30mph. This might be because of a similar reason for single carriageway road accidents.
On roundabouts, 17,982 accidents have been recorded from which 10,969 happened in areas with a speed limit of 30mph. From this data, we can identify a pattern of most accidents happening in busy areas with lower speed limits because of the traffic. On a one-way street, 6,745 numbers of accidents were recorded again with most accidents happening in areas where the speed limit was 30mph. The least number of accidents took place on slip roads with a total number of 3,833, which might be because of people not giving way or slowing down.
These numbers and findings are affected by how many vehicles normally drive on the different road types which would improve the accuracy of the results but that is indeed difficult to record.