<informationTable xmlns="http://www.sec.gov/edgar/document/thirteenf/informationtable">		<infoTable>
			<nameOfIssuer>ABBVIE INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>00287Y109</cusip>
			<value>24174</value>
			<shrsOrPrnAmt>
				<sshPrnamt>255400</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>255400</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ABBOTT LABS</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>002824100</cusip>
			<value>15304</value>
			<shrsOrPrnAmt>
				<sshPrnamt>255400</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>255400</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>COLGATE PALMOLIVE CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>194162103</cusip>
			<value>29994</value>
			<shrsOrPrnAmt>
				<sshPrnamt>418450</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>418450</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ISHARES TR</nameOfIssuer>
			<titleOfClass>SELECT DIVID ETF</titleOfClass>
			<cusip>464287168</cusip>
			<value>176704</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1857700</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1857700</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ISHARES TR</nameOfIssuer>
			<titleOfClass>RUS 1000 ETF</titleOfClass>
			<cusip>464287622</cusip>
			<value>270167</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1840000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1840000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ISHARES TR</nameOfIssuer>
			<titleOfClass>MIN VOL USA ETF</titleOfClass>
			<cusip>46429B697</cusip>
			<value>279270</value>
			<shrsOrPrnAmt>
				<sshPrnamt>5376772</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>5376772</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>ISHARES TR</nameOfIssuer>
			<titleOfClass>CORE S&amp;P500 ETF</titleOfClass>
			<cusip>464287200</cusip>
			<value>309275</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1165800</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1165800</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>JOHNSON &amp; JOHNSON</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>478160104</cusip>
			<value>38791</value>
			<shrsOrPrnAmt>
				<sshPrnamt>302700</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>302700</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>COCA COLA CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>191216100</cusip>
			<value>24511</value>
			<shrsOrPrnAmt>
				<sshPrnamt>564384</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>564384</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MARSH &amp; MCLENNAN COS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>571748102</cusip>
			<value>433218</value>
			<shrsOrPrnAmt>
				<sshPrnamt>5245400</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>5245400</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>MERCK &amp; CO INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>58933Y105</cusip>
			<value>30906</value>
			<shrsOrPrnAmt>
				<sshPrnamt>567400</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>567400</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>PFIZER INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>717081103</cusip>
			<value>36679</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1033500</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1033500</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>PRINCIPAL FINL GROUP INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>74251V102</cusip>
			<value>1104725</value>
			<shrsOrPrnAmt>
				<sshPrnamt>18137000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>18137000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>PROCTER AND GAMBLE CO</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>742718109</cusip>
			<value>23724</value>
			<shrsOrPrnAmt>
				<sshPrnamt>299245</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>299245</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>PRUDENTIAL FINL INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>744320102</cusip>
			<value>265088</value>
			<shrsOrPrnAmt>
				<sshPrnamt>2560000</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>2560000</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SELECT SECTOR SPDR TR</nameOfIssuer>
			<titleOfClass>SBI INT-INDS</titleOfClass>
			<cusip>81369Y704</cusip>
			<value>138317</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1861600</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1861600</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SELECT SECTOR SPDR TR</nameOfIssuer>
			<titleOfClass>TECHNOLOGY</titleOfClass>
			<cusip>81369Y803</cusip>
			<value>134104</value>
			<shrsOrPrnAmt>
				<sshPrnamt>2049900</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>2049900</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SELECT SECTOR SPDR TR</nameOfIssuer>
			<titleOfClass>SBI CONS STPLS</titleOfClass>
			<cusip>81369Y308</cusip>
			<value>57740</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1097100</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1097100</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SELECT SECTOR SPDR TR</nameOfIssuer>
			<titleOfClass>SBI HEALTHCARE</titleOfClass>
			<cusip>81369Y209</cusip>
			<value>92671</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1138600</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1138600</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SELECT SECTOR SPDR TR</nameOfIssuer>
			<titleOfClass>SBI CONS DISCR</titleOfClass>
			<cusip>81369Y407</cusip>
			<value>103589</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1022600</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1022600</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>SPDR S&amp;P 500 ETF TR</nameOfIssuer>
			<titleOfClass>TR UNIT</titleOfClass>
			<cusip>78462F103</cusip>
			<value>378124</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1435060</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1435060</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>VANGUARD WORLD FD</nameOfIssuer>
			<titleOfClass>MEGA CAP INDEX</titleOfClass>
			<cusip>921910873</cusip>
			<value>10499</value>
			<shrsOrPrnAmt>
				<sshPrnamt>115900</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>115900</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>VANGUARD INDEX FDS</nameOfIssuer>
			<titleOfClass>S&amp;P 500 ETF SHS</titleOfClass>
			<cusip>922908363</cusip>
			<value>317940</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1313749</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1313749</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>VANGUARD INDEX FDS</nameOfIssuer>
			<titleOfClass>TOTAL STK MKT</titleOfClass>
			<cusip>922908769</cusip>
			<value>118366</value>
			<shrsOrPrnAmt>
				<sshPrnamt>872200</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>872200</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>VANGUARD INDEX FDS</nameOfIssuer>
			<titleOfClass>LARGE CAP ETF</titleOfClass>
			<cusip>922908637</cusip>
			<value>31345</value>
			<shrsOrPrnAmt>
				<sshPrnamt>258600</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>258600</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
		<infoTable>
			<nameOfIssuer>VERIZON COMMUNICATIONS INC</nameOfIssuer>
			<titleOfClass>COM</titleOfClass>
			<cusip>92343V104</cusip>
			<value>50780</value>
			<shrsOrPrnAmt>
				<sshPrnamt>1061900</sshPrnamt>
				<sshPrnamtType>SH</sshPrnamtType>
			</shrsOrPrnAmt>
			<investmentDiscretion>SOLE</investmentDiscretion>
			<votingAuthority>
				<Sole>1061900</Sole>
				<Shared>0</Shared>
				<None>0</None>
			</votingAuthority>
		</infoTable>
</informationTable>
