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  <xsd:element id="mcy_CapitalContributionsToSubsidiaries" name="CapitalContributionsToSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_CommercialAutomobileMember" name="CommercialAutomobileMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_CommonStockTypeAxis" name="CommonStockTypeAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_CommonStockTypeDomain" name="CommonStockTypeDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_CostEquitySecurityTradingInvestments" name="CostEquitySecurityTradingInvestments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_CostShortTermInvestments" name="CostShortTermInvestments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcy_CreditFacilityMember" name="CreditFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_DecreaseInProvisionForInsuredEvents" name="DecreaseInProvisionForInsuredEvents" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcy_DeferredTaxLiabilitiesAcquisitionCosts" name="DeferredTaxLiabilitiesAcquisitionCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcy_DeferredTaxLiabilitiesTaxAmortizationInExcessOfBookAmortization" name="DeferredTaxLiabilitiesTaxAmortizationInExcessOfBookAmortization" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcy_DeferredTaxLiabilitiesUndistributedInsuranceSubsidiaries" name="DeferredTaxLiabilitiesUndistributedInsuranceSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcy_DerivativeFinancialInstrumentsLineItems" name="DerivativeFinancialInstrumentsLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_DerivativeFinancialInstrumentsTable" name="DerivativeFinancialInstrumentsTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_DividendsAndStatutoryRestrictionsTableTextBlock" name="DividendsAndStatutoryRestrictionsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_DividendsReceivedFromSubsidiaries" name="DividendsReceivedFromSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_EarningsPerShareTable" name="EarningsPerShareTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_EnergyAndOtherMember" name="EnergyAndOtherMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_EquityContractsFinancialInstrumentsLiabilitiesFairValueDisclosure" name="EquityContractsFinancialInstrumentsLiabilitiesFairValueDisclosure" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcy_EstimatedFairValuesOfInvestmentsTableTextBlock" name="EstimatedFairValuesOfInvestmentsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_ExercisePriceRangeFromFiftyTwoPointOneThreeToFiftyEightPointEightThreeMember" name="ExercisePriceRangeFromFiftyTwoPointOneThreeToFiftyEightPointEightThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_ExercisePriceRangeFromFortySevenPointSixOneToFiftyOnePointFiveOneMember" name="ExercisePriceRangeFromFortySevenPointSixOneToFiftyOnePointFiveOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_ExercisePriceRangeFromThirtyThreePointSixOneToFortyPointFiveThreeMember" name="ExercisePriceRangeFromThirtyThreePointSixOneToFortyPointFiveThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_FairValueAssetsMeasuredOnRecurringBasis" name="FairValueAssetsMeasuredOnRecurringBasis" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_FairValueLiabilitiesMeasuredOnRecurringBasis" name="FairValueLiabilitiesMeasuredOnRecurringBasis" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcy_FairValueMeasurementLineItems" name="FairValueMeasurementLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_FairValueMeasurementTable" name="FairValueMeasurementTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_FairValueOptionAbstract" name="FairValueOptionAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_FairValueQualitativeDisclosuresRelatedToElectionByEligibleItemOrGroupAxis" name="FairValueQualitativeDisclosuresRelatedToElectionByEligibleItemOrGroupAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_FairValueQualitativeDisclosuresRelatedToElectionByEligibleItemOrGroupDomain" name="FairValueQualitativeDisclosuresRelatedToElectionByEligibleItemOrGroupDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_FederalIncomeTaxExpenseAbstract" name="FederalIncomeTaxExpenseAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_FurnitureEquipmentAndPurchaseSoftwareMember" name="FurnitureEquipmentAndPurchaseSoftwareMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_HomeownersMember" name="HomeownersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_IncomeTaxPayableDueToAffiliate" name="IncomeTaxPayableDueToAffiliate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcy_IncomeTaxReceivableDueFromAffiliate" name="IncomeTaxReceivableDueFromAffiliate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_IncreaseInProvisionForInsuredEvents" name="IncreaseInProvisionForInsuredEvents" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcy_LossBeforeEquityInNetIncomeLossOfSubsidiaries" name="LossBeforeEquityInNetIncomeLossOfSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcy_LossesAndLossAdjustmentExpensesPolicyTextBlock" name="LossesAndLossAdjustmentExpensesPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_MaximumPercentageOfCompensationEmployeeIsAllowedToContribute" name="MaximumPercentageOfCompensationEmployeeIsAllowedToContribute" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_MccMember" name="MccMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_NetRealizedInvestmentGainsMember" name="NetRealizedInvestmentGainsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_NumberOfInstancesOfNonComplianceIssuedFromRegulatoryBody" name="NumberOfInstancesOfNonComplianceIssuedFromRegulatoryBody" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_NumberOfKnowledgeableOutsideSecurityBrokersConsultedToDetermineFairValue" name="NumberOfKnowledgeableOutsideSecurityBrokersConsultedToDetermineFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:positiveIntegerItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_NumberOfSubsidiaries" name="NumberOfSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_OptionAndShortSaleTransactionsMember" name="OptionAndShortSaleTransactionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_OptionsGrantedPriorToTwoThousandEightMember" name="OptionsGrantedPriorToTwoThousandEightMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_OptionsGrantedSubsequentToJanuaryOneTwoThousandEightMember" name="OptionsGrantedSubsequentToJanuaryOneTwoThousandEightMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_OtherLinesMember" name="OtherLinesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_PartnershipInterestInPrivateCreditFundMember" name="PartnershipInterestInPrivateCreditFundMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PaymentsOfExtraordinaryDividends" name="PaymentsOfExtraordinaryDividends" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcy_PercentageByWhichDividendIncomeOnNonRedeemablePreferredStockPartnershipCommonStockIsPartiallyTaxSheltered" name="PercentageByWhichDividendIncomeOnNonRedeemablePreferredStockPartnershipCommonStockIsPartiallyTaxSheltered" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PercentageOfDirectPremiumsWrittenAsPrivatePassengerAutomobileLinesOfInsurance" name="PercentageOfDirectPremiumsWrittenAsPrivatePassengerAutomobileLinesOfInsurance" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PercentageOfFixedMaturitySecurities" name="PercentageOfFixedMaturitySecurities" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PercentageOfLargestAmountOfTaxBenefitRealized" name="PercentageOfLargestAmountOfTaxBenefitRealized" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PercentageOfPrivatePassengerAutomobilePremiumsWrittenInCalifornia" name="PercentageOfPrivatePassengerAutomobilePremiumsWrittenInCalifornia" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PercentageOfSpecificUnadjustedBrokerQuotesObtained" name="PercentageOfSpecificUnadjustedBrokerQuotesObtained" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PercentageOfStockOptionExercisablePerYear" name="PercentageOfStockOptionExercisablePerYear" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PercentageOfUnadjustedFairValueObtained" name="PercentageOfUnadjustedFairValueObtained" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PerformanceVestingRestrictedStockUnitsThreeYearPerformancePeriodEndingYears" name="PerformanceVestingRestrictedStockUnitsThreeYearPerformancePeriodEndingYears" nillable="true" substitutionGroup="xbrli:item" type="xbrli:gYearItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PerformanceVestingRestrictedStockUnitsVestingSharesMaximum" name="PerformanceVestingRestrictedStockUnitsVestingSharesMaximum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_PrivateCreditFundMember" name="PrivateCreditFundMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_PrivatePassengerAutomobileMember" name="PrivatePassengerAutomobileMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_ProceedsFromCallsOfAvailableForSaleSecurities" name="ProceedsFromCallsOfAvailableForSaleSecurities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcy_ProceedsFromDividendsReceivedFromSubsidiaries" name="ProceedsFromDividendsReceivedFromSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_PublicUtilitiesMember" name="PublicUtilitiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_ReissuanceRecoverable" name="ReissuanceRecoverable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcy_RestrictedStockAndRestrictedStockUnitMember" name="RestrictedStockAndRestrictedStockUnitMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_RestructuringAndRelatedCostsNumberOfPositionsEliminatedPercentageOfTotalWorkforce" name="RestructuringAndRelatedCostsNumberOfPositionsEliminatedPercentageOfTotalWorkforce" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_RisksAndUncertaintiesTextBlock" name="RisksAndUncertaintiesTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_ScheduleDirectPremiumsAttributableToSegmentTableTextBlock" name="ScheduleDirectPremiumsAttributableToSegmentTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_ScheduleOfCondensedComprehensiveIncomeStatementTableTextBlock" name="ScheduleOfCondensedComprehensiveIncomeStatementTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_ScheduleOfDeferredPolicyAcquisitionCostsTableTextBlock" name="ScheduleOfDeferredPolicyAcquisitionCostsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_ScheduleOfDerivativeGainsAndLossesInConsolidatedStatementsOfOperationsTableTextBlock" name="ScheduleOfDerivativeGainsAndLossesInConsolidatedStatementsOfOperationsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_ScheduleOfDividendsPaidInTotalAndPerShareTableTextBlock" name="ScheduleOfDividendsPaidInTotalAndPerShareTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_ScheduleOfShareBasedCompensationArrangementTable" name="ScheduleOfShareBasedCompensationArrangementTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_ScheduleOfStatutoryNetIncomeAndCapitalAndSurplusTableTextBlock" name="ScheduleOfStatutoryNetIncomeAndCapitalAndSurplusTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_SecuredNoteNo1Member" name="SecuredNoteNo1Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_SecuredNoteNo2Member" name="SecuredNoteNo2Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_SecurityDepositsByInsuranceCompanies" name="SecurityDepositsByInsuranceCompanies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedInPeriodTotalFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedInPeriodTotalFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_StateIncomeTaxExpenseAbstract" name="StateIncomeTaxExpenseAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_StatutoryBalancesAndAccountingPracticesAbstract" name="StatutoryBalancesAndAccountingPracticesAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_StatutoryBalancesAndAccountingPracticesLineItems" name="StatutoryBalancesAndAccountingPracticesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_StatutoryBalancesAndAccountingPracticesTable" name="StatutoryBalancesAndAccountingPracticesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_StockOptionExpirationPeriod" name="StockOptionExpirationPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_SummaryOfSignificantAccountingPoliciesLineItems" name="SummaryOfSignificantAccountingPoliciesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_SummaryOfSignificantAccountingPoliciesTable" name="SummaryOfSignificantAccountingPoliciesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_TradingSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue" name="TradingSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_TradingSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue" name="TradingSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_TradingSecuritiesDebtMaturitiesAfterTenYearsFairValue" name="TradingSecuritiesDebtMaturitiesAfterTenYearsFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_TradingSecuritiesDebtMaturitiesWithinOneYearFairValue" name="TradingSecuritiesDebtMaturitiesWithinOneYearFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_TradingSecuritiesEquityCost" name="TradingSecuritiesEquityCost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_TradingSecuritiesShortTermInvestmentsAmortizedCost" name="TradingSecuritiesShortTermInvestmentsAmortizedCost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcy_TwoThousandFivePlanMember" name="TwoThousandFivePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_UnfavorableDevelopment" name="UnfavorableDevelopment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_UnionBankMember" name="UnionBankMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
