Determinants of Claim Frequency in CTP Schemes. Raewin Davies, Jack Jiang and Rosi Winn

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1 Determinants of Claim Frequency in CTP Schemes Raewin Davies, Jack Jiang and Rosi Winn

2 Background A reducing trend in casualty rates for most states and territories over the past decade This contributes reduction in CTP claims for most states Developed a framework to analysis the drivers of reductions in both casualty rates and claim frequency

in CTP claims for most states Developed a framework to analysis

3 Casualties by State Changes in casualties per 1000 vehicles by State, Base year = Accident Year Ending 31-Dec NSW VIC QLD ACT SA NT

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

4 Claim Frequency by State 120 Change in Claim Frequency by State Base year = NSW VIC QLD ACT NT Accident Year Ending 31-Dec

QLD ACT NT 50 40 1990 1991 1992 1993 1994 1995 1996

5 General Framework Development of a CTP claim Factors influencing transport accident claims

6 Development of a CTP claim Accidents Non-casualty accidents Casualties At Fault Casualties Third Party Casualties Non-claimants Claimants * Based on an at-fault scheme design

7 Main factors Road Safety Design speed limits road surface quality Number and Severity of Accidents Number of vehicles on road Weather Conditions Rain Ice Fog Number and Severity of Casualties Mix of road users balance of cars, motorbikes, pedestrians etc in different areas Vehicle Safety Seat belts Airbags General design Driver Behaviours Alcohol Fatigue Use of seat belts Driving skills Number and Severity of Third Party Casualties Number of CTP Claims Number of passengers per vehicle Propensity to Claim Benefits available Benefit alternatives Medicare etc Judicial attitudes Claimant attitudes

Airbags General design Driver Behaviours Alcohol Fatigue Use of seat belts Driving skills Number and Severity of Third Party Casualties Number of CTP

8 Accidents NSW accident rate Accidents / 1000 vehicles Year Actual Fitted

9 Influence of Alcohol RBTs per 1000 vehicles NSW - Random breath testing Stationary Mobile % fail - stationary % fail - mobile 4.00% 3.50% 3.00% 2.50% 2.00% 1.50% 1.00% 0.50% 0.00% Failure rate

1996 1997 1998 1999 Stationary Mobile % fail - stationary % fail -

10 Influence of Alcohol NSW - Alcohol involvement in accidents Yes Unknown No

11 Influence of Alcohol NSW - Fatal crashes and RBT failues 1.50% 1.25% 1.00% 0.75% 0.50% 0.25% 0.00% Fatal crashes involving alcohol % Fail RBT Fatal % fail total (weighted)

12 Casualties NSW - Fatalities and casualties per accident Fatality rate Year Casualty rate Fatalities Casualties

0050 0.0000 1976 1981 1986 1991 1996 2001 Year 0.7 0.

13 Car Safety Measures

14 Car Safety Measures Crashworthiness by vehicle type Small Medium Large Significantly better Better than average Average Worse than average Significantly worse 4 WD 0% 20% 40% 60% 80% 100% % of vehicles by make of vehicle

average Average Worse than average Significantly worse

15 Car Safety Measures Aggressivity by vehicle type Small Medium Large Significantly better Better than average Average Worse than average Significantly worse 4 WD 0% 20% 40% 60% 80% 100% % of vehicles by make of vehicle

Average Worse than average Significantly worse 4 WD 0%

16 Casualties per accident by road user NSW - Casualties per accident by road user Year Driver Passenger Motor cyclist Pedestrian Pedal cyclist

17 Casualties per accident by road user 125% NSW - % change in casualties per accident 100% 75% 50% 25% 0% % % Year Driver Passenger Motor cyclist Pedestrian Pedal cyclist

0% 1976-25% 1981 1986 1991 1996 2001-50% Year

18 Casualties per accident by road user NSW - Driver and passenger casualties 18,000 16,000 14,000 12,000 10,000 8,000 6,000 4,000 2, Driver Passenger

12,000 10,000 8,000 6,000 4,000 2,000 0 1960 1965

19 CTP Claims NSW - s74 claims per casualty by road user Legislative changes New Act Driver Passenger Motor cyclist Pedestrian Pedal cyclist

30 Motor cyclist Pedestrian Pedal cyclist 0.20 0.10 0.

20 CTP Claims Change in S74 claim rate (relative to claim rate) 30% 20% 10% 0% -10% % -30% -40% -50% Driver Passenger Motor cyclist Pedestrian Pedal cyclist

1995 1996 1997 1998 1999 2000 2001 2002 2003-20% -30% -40%

21 Influence of Rainfall Hypothesised recent drought may be contributing factor to low claim frequencies Created daily set of claim and rainfall data by region Covered period , NSW only Used data to do a number of analyses to understand effect of rainfall on claims

22 Sydney Region: Box plot for each decile

23 Sydney Region: Plot of Daily Claims vs Rainfall 21 Average Number of Claims Rainfall

24 Correlations Variable Daily Rainfall Log (1+daily rainfall) Sev 0 claims Sev 1 claims Sev 2 claims Sev 3 claims Sev 4 claims Sev 5 claims Sev 6 claims All claims

25 Matched Sampling Match data for cases of poor weather with suitable control event where weather was good Eg match a rainy Monday in February with a dry Monday in that February to provide an event control pair Compare accident experiences for periods with adverse conditions with control periods The estimate of the effect of the adverse factor is based on the combined data from many eventcontrol pairs

26 Matched Sampling Results Sydney Event-Control Ratio for Sydney Claims Sydney Region Ratio of Event to Control Claim Numbers 140% 130% Severity mm mm 5 15 mm mm 120% Severity 0 & % 100% Severity 2 & % Severity 4, 5 & % All claims % 60% 50% Severity 0 & 1 Severity 2 & 3 Severity 4, 5 & 6 All Claims Rainfall mm Rainfall mm Rainfall 5-15 mm Rainfall 15 mm +

27 Matched Sampling Results All Regions in NSW Event-Control Ratio for All Claims 150% All Regions Ratio of Event to Control Claim Numbers 140% 130% 120% Severity mm mm 5 15 mm 15 + mm 110% Severity 0 & % Severity 2 & % Severity 4, 5 & % All claims % 60% 50% Severity 0 & 1 Severity 2 & 3 Severity 4, 5 & 6 All Claims Rainfall mm Rainfall mm Rainfall 5-15 mm Rainfall 15 mm +

28 Impact on Claim Frequency Has the level of rainfall had a significant impact on the claim frequency reductions that we have observed in recent years? Total Annual Rainfall (m) average Year

29 1.5% 1.0% 0.5% 0.0% -0.5% -1.0% Frequency Variations Year Difference to Average

30 Summary Accidents dramatically reduced between 1975 and 1992 Slower reduction in accidents since then Clear correlation between RBTs and fatal accidents Improvements in vehicle crashworthiness broadly consistent with declines in fatalities Increases from late 1990s appears partially attributable to increased use of 4WDs Unable to explain divergence between casualty for drivers and passengers There is some correlation between daily claim numbers and rainfall but has relatively small impact over any year

Determinants of Claim Frequency In CTP Schemes

- 1 - Determinants of Claim Frequency In CTP Schemes Prepared by Raewin Davies, Rosi Winn and Jack Jiang Presented to the Institute of Actuaries of Australia Accident Compensation Seminar 28 November to