Assumptions about future events are a necessary component of the actuarial valuations. Key among them are:

•  Members' future rates of retirement and disability.

•  Their total length of service.

•  The rate at which their salaries will increase. 

OSA performs experience studies at least once every six years to determine at what rate the above factors have actually occurred in the retirement systems.  We compare actual rates to the assumptions and, if necessary, we make adjustments to the rates for future valuations.


Click on the titles below to open the PDF.

2007-2012 Demographic Experience Study [7.6MB]

Report may take 5-10 minutes to load, individual sections are below.

Letter of Introduction [732KB]

Section 1:  Executive Summary [248KB]

Section 2:  Development of Demographic Assumptions[1.6MB]

Actuarial Certification Letter [237KB]

Mortality Rates[530KB]

Retirement Rates [242KB]

Disability Rates [338KB]

Termination Rates [315KB]

Service-Based Salary Increases [350KB]

Section 3:  Appendices [3.3MB]

Results by System

Retirement Rates [497KB]

Disability Rates [522KB]

Termination Rates [431KB]

Service-Based Salary Increases [470KB]

Miscellaneous Assumptions

Percent Vested [519KB]

Survivors Selecting Annuities [558KB]

AFC Load [487KB]

Certain and Life Annuities [366KB]

Military Service Credit Load [433KB]

Age Difference [393KB]

Replacement Salaries [455KB]

Percent Male/Female [354KB]

WSPRS Disabled Life Expectancy [301KB]

LEOFF 1 Dependent Children [269KB]

Percent Fire Fighter & Cat. Dis. Benefit in LEOFF 2 [344KB]

Deferred Annuity Assumption [297KB]

Minimum and Maximum Age [303KB]

Duty Death Assumption [368KB]

TRS Salary Bonus Reviews [352KB]

Section 4:  Glossary  [261KB]

See also our online Glossary.


Historical Experience Study:  2001-2006 Demographic Experience Study [2.4MB].

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