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        <EOYAmt>260561</EOYAmt>
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        <EOYAmt>594309</EOYAmt>
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        <EOYAmt>854870</EOYAmt>
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      <ReconcilationRevenueExpnssAmt>-460557</ReconcilationRevenueExpnssAmt>
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      <MethodOfAccountingAccrualInd>X</MethodOfAccountingAccrualInd>
      <AccountantCompileOrReviewInd>0</AccountantCompileOrReviewInd>
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      <AuditCommitteeInd>0</AuditCommitteeInd>
      <FederalGrantAuditRequiredInd>0</FederalGrantAuditRequiredInd>
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        <ContributorBusinessName>
          <BusinessNameLine1>RESTRICTED</BusinessNameLine1>
        </ContributorBusinessName>
        <ContributorUSAddress>
          <AddressLine1>RESTRICTED</AddressLine1>
          <AddressLine2>RESTRICTED</AddressLine2>
          <City>RESTRICTED</City>
          <State>RESTRICTED</State>
          <ZIPCode>RESTRICTED</ZIPCode>
        </ContributorUSAddress>
        <TotalContributionsAmt>RESTRICTED</TotalContributionsAmt>
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      <OnlyInHouseLobbyingInd>0</OnlyInHouseLobbyingInd>
      <AgreeCarryoverPriorYearInd>1</AgreeCarryoverPriorYearInd>
      <DuesAssessmentsAmt>1003321</DuesAssessmentsAmt>
      <NonDeductibleLbbyngPltclCYAmt>64507</NonDeductibleLbbyngPltclCYAmt>
      <NonDedLbbyngPltclCyovAmt>-2676646</NonDedLbbyngPltclCyovAmt>
      <NonDeductibleLbbyngPltclTotAmt>-2612139</NonDeductibleLbbyngPltclTotAmt>
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      <CarriedOverAmt>-2913135</CarriedOverAmt>
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        <DepreciationAmt>43600</DepreciationAmt>
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      <FootnoteTextInd>X</FootnoteTextInd>
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      <RevenueNotReportedAmt>0</RevenueNotReportedAmt>
      <RevenueSubtotalAmt>1099716</RevenueSubtotalAmt>
      <RevenueNotReportedFinclStmtAmt>0</RevenueNotReportedFinclStmtAmt>
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      <ExpensesNotRptFinclStmtAmt>0</ExpensesNotRptFinclStmtAmt>
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      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>PART X, LINE 2:</FormAndLineReferenceDesc>
        <ExplanationTxt>SIRC EVALUATED ITS UNCERTAINTY IN INCOME TAXES FOR THE YEAR ENDED DECEMBER 31, 2024, AND DETERMINED THAT THERE WERE NO MATTERS THAT WOULD REQUIRE RECOGNITION IN THE FINANCIAL STATEMENTS OR THAT MAY HAVE ANY EFFECT ON ITS TAX-EXEMPT STATUS; AND THERE ARE CURRENTLY NO AUDITS PENDING OR IN PROGRESS.</ExplanationTxt>
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      <WrittenPolicyRefTAndEExpnssInd>1</WrittenPolicyRefTAndEExpnssInd>
      <SubstantiationRequiredInd>1</SubstantiationRequiredInd>
      <BoardOrCommitteeApprovalInd>X</BoardOrCommitteeApprovalInd>
      <SeverancePaymentInd>0</SeverancePaymentInd>
      <SupplementalNonqualRtrPlanInd>0</SupplementalNonqualRtrPlanInd>
      <EquityBasedCompArrngmInd>0</EquityBasedCompArrngmInd>
      <RltdOrgOfficerTrstKeyEmplGrp>
        <PersonNm>RAY EHRLICH</PersonNm>
        <TitleTxt>EXECUTIVE DIRECTOR</TitleTxt>
        <BaseCompensationFilingOrgAmt>187280</BaseCompensationFilingOrgAmt>
        <CompensationBasedOnRltdOrgsAmt>0</CompensationBasedOnRltdOrgsAmt>
        <BonusFilingOrganizationAmount>0</BonusFilingOrganizationAmount>
        <BonusRelatedOrganizationsAmt>0</BonusRelatedOrganizationsAmt>
        <OtherCompensationFilingOrgAmt>0</OtherCompensationFilingOrgAmt>
        <OtherCompensationRltdOrgsAmt>0</OtherCompensationRltdOrgsAmt>
        <DeferredCompensationFlngOrgAmt>6312</DeferredCompensationFlngOrgAmt>
        <DeferredCompRltdOrgsAmt>0</DeferredCompRltdOrgsAmt>
        <NontaxableBenefitsFilingOrgAmt>22913</NontaxableBenefitsFilingOrgAmt>
        <NontaxableBenefitsRltdOrgsAmt>0</NontaxableBenefitsRltdOrgsAmt>
        <TotalCompensationFilingOrgAmt>216505</TotalCompensationFilingOrgAmt>
        <TotalCompensationRltdOrgsAmt>0</TotalCompensationRltdOrgsAmt>
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        <CompReportPrior990RltdOrgsAmt>0</CompReportPrior990RltdOrgsAmt>
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      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>PART I, LINE 1A</FormAndLineReferenceDesc>
        <ExplanationTxt>SIRC REIMBURSES THE HEALTH INSURANCE PREMIUMS FOR ITS EXECUTIVE DIRECTOR AND INCLUDES THOSE PAYMENTS IN TAXABLE INCOME ON THE INDIVIDUAL'S FORM W-2. SIRC GROSSES UP THE PAYMENTS TO COVER THE ADDITIONAL PAYROLL TAX ON THIS TAXABLE INCOME.</ExplanationTxt>
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    </IRS990ScheduleJ>
    <IRS990ScheduleO documentId="RetDoc1044400001">
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION A, LINE 6</FormAndLineReferenceDesc>
        <ExplanationTxt>ANY COMPANY WITH FACILITIES IN NORTH AMERICA THAT MANUFACTURES OR PROCESSES ETHYLBENZENE OR STYRENE MONOMER IS ELIGIBLE TO BECOME A VOTING MEMBER OF THE ORGANIZATION. COMPANIES WHICH FABRICATE MATERIALS FROM DERIVATIVES OF ETHYLBENZENE OR STYRENE, WITHIN OR OUTSIDE OF NORTH AMERICA, ARE ELIGIBLE TO BECOME ASSOCIATE, NON-VOTING MEMBERS OF THE ORGANIZATION.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION A, LINE 7A</FormAndLineReferenceDesc>
        <ExplanationTxt>THE ORGANIZATION'S MEMBERS ANNUALLY ELECT THE VOTING OFFICERS OF THE ORGANIZATION.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION A, LINE 8B</FormAndLineReferenceDesc>
        <ExplanationTxt>WRITTEN MINUTES ARE PREPARED FOR ALL BOARD MEETINGS AND ARE REVIEWED AND FORMALLY ACCEPTED BY THE BOARD AT THE SUBSEQUENT BOARD MEETING. THE BOARD HAS NO FORMAL COMMITTEES FOR WHICH SEPARATE WRITTEN MINUTES ARE DOCUMENTED.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION B, LINE 11B</FormAndLineReferenceDesc>
        <ExplanationTxt>THE FEDERAL FORM 990 IS REVIEWED BY THE ORGANIZATION'S EXECUTIVE DIRECTOR. SUCH REVIEW TAKES PLACE UPON RECEIPT OF THE DRAFT FORM 990 RECEIVED FROM THE INDEPENDENT PUBLIC ACCOUNTING FIRM WHO CONDUCTS THE ORGANIZATION'S FINANCIAL STATEMENT AUDIT AND INVOLVES COMPARISON OF FINANCIAL DATA IN THE FORM 990 WITH THE AUDITED FINANCIAL STATEMENTS AND REVIEW OF ALL NARRATIVE INFORMATION FOR ACCURACY AND COMPLETENESS. A COPY OF THE FORM 990 IS FORWARDED TO VOTING MEMBERS OF THE BOARD PRIOR TO THE FILING OF THE FORM 990.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION B, LINE 12</FormAndLineReferenceDesc>
        <ExplanationTxt>THE ORGANIZATION, IN CONJUNCTION WITH OUTSIDE COUNSEL, REGULARLY REVIEWS ANTI-TRUST PROVISIONS, WHICH SPECIFICALLY ADDRESS CONFLICT OF INTEREST PROVISIONS, AT BOARD MEETINGS.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION B, LINE 15</FormAndLineReferenceDesc>
        <ExplanationTxt>FORM 990, PART VI, SECTION B, LINE 15A: THE STEERING COMMITTEE (THE GOVERNING BODY) ANNUALLY REVIEWS THE PERFORMANCE OF THE EXECUTIVE DIRECTOR AND APPROVES THE EXECUTIVE DIRECTOR'S COMPENSATION.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART VI, SECTION C, LINE 19</FormAndLineReferenceDesc>
        <ExplanationTxt>THE ORGANIZATION MAKES ITS GOVERNING DOCUMENTS AND FINANCIAL STATEMENTS AVAILABLE UPON REQUEST.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990, PART IX, LINE 11G</FormAndLineReferenceDesc>
        <ExplanationTxt>GENERAL CONSULTING AND SCIENCE STUDIES 879,528. RESEARCH PUBLISHING AND STORAGE 29,921. OTHER PROFESSIONAL FEES 7,472.</ExplanationTxt>
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</Return>