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WORLD EQUITY EX-US FUND SIIT Screened World Equity Ex-US Fund SIIT EMERGING MARKETS EQUITY FUND SIIT Opportunistic Income Fund SIIT CORE FIXED INCOME SIIT HIGH YIELD BOND FUND SIIT LONG DURATION FUND SIIT Long Duration Credit Fund SIIT Ultra Short Duration Bond Fund SIIT EMERGING MARKETS DEBT FUND SIIT Real Return Fund SIIT Limited Duration Bond Fund SIIT Intermediate Duration Credit Fund SIIT Dynamic Asset Allocation Fund SIIT Multi-Asset Real Return Fund SIIT LARGE CAP FUND - CLASS A SIIT LARGE CAP DISCIPLINED EQUITY FUND - CLASS A SIIT LARGE CAP INDEX FUND - CLASS A SIIT S&P 500 Index Fund - Class A SIIT Extended Market Index Fund - Class A SIIT SMALL CAP FUND - CLASS A SIIT Small Cap II Fund - Class A SIIT SMALL MID CAP EQUITY FUND - CLASS A SIIT U.S. Equity Factor Allocation Fund - Class A SIIT U.S. Managed Volatility Fund - Class A SIIT Global Managed Volatility Fund - Class A SIIT WORLD EQUITY EX-US FUND - CLASS A SIIT Screened World Equity Ex-US Fund - Class A SIIT EMERGING MARKETS EQUITY FUND - CLASS A SIIT Opportunistic Income Fund - Class A SIIT CORE FIXED INCOME - CLASS A SIIT HIGH YIELD BOND FUND - CLASS A SIIT LONG DURATION FUND - CLASS A SIIT Long Duration Credit Fund - Class A SIIT Ultra Short Duration Bond Fund - Class A SIIT EMERGING MARKETS DEBT FUND - CLASS A SIIT Real Return Fund - Class A SIIT Limited Duration Bond Fund - Class A SIIT Intermediate Duration Credit Fund - Class A SIIT Dynamic Asset Allocation Fund - Class A SIIT Multi-Asset Real Return Fund - Class A Equity Market Risk [Member] Fixed Income Market Risk [Member] Market Risk [Member] Inflation Protected Securities Risk [Member] Below Investment Grade Securities (Junk Bonds) Risk [Member] Foreign Investment/Emerging and Frontier Markets Risk [Member] Country Concentration Risk [Member] Risk of Investing in China [Member] Large Capitalization Risk [Member] Small and Medium Capitalization Companies Risk [Member] Quantitative Investing Risk [Member] Investment Style Risk [Member] U.S. Government Securities Risk [Member] Below Investment Grade Securities Risk [Member] Foreign Investment/Emerging Markets Risk [Member] Foreign Sovereign Debt Securities Risk [Member] Municipal Securities Risk [Member] Bank Loans Risk [Member] Corporate Fixed Income Securities Risk [Member] Commercial Paper Risk [Member] Investing in Limited Recourse Obligations Risk [Member] Private Placements Risk [Member] Social Investment Criteria Risk [Member] Tracking Error Risk [Member] Sampling Risk [Member] Preferred Stock Risk [Member] Depositary Receipts Risk [Member] Convertible and Preferred Securities Risk [Member] Warrants Risk [Member] Tax Risk [Member] Participation Notes (P-Notes) Risk [Member] American Depositary Receipts (ADRs) Risk [Member] Exchange-Traded Funds Risk [Member] Foreign Investment Risk [Member] Currency Risk [Member] Inflation Protected Securities [Member] REITs Risk [Member] Small Capitalization Risk [Member] Structured Securities Risk [Member] Small and Medium Capitalization Risk [Member] Short Sales Risk [Member] Real Estate Industry Risk [Member] Derivatives Risk [Member] Commodity-Linked Securities Risk [Member] Investment Company Risk [Member] Investment in the Subsidiary Risk [Member] Commodity Investments and Derivatives Risk [Member] Long/Short Risk [Member] Repurchase Agreements and Reverse Repurchase Agreements Risk [Member] Asset-Backed Securities Risk [Member] Mortgage-Backed Securities Risk [Member] Mortgage Dollar Rolls Risk [Member] Foreign Investment and Foreign Issuer Risk [Member] Liquidity Risk [Member] Leverage Risk [Member] Redemption Risk [Member] Opportunity Risk [Member] Duration Risk [Member] Extension Risk [Member] Portfolio Turnover Risk [Member] Interest Rate Risk [Member] Money Market Funds [Member] Credit Risk [Member] Prepayment Risk [Member] S&P 500 Index Return (reflects no deduction for fees, expenses or taxes) Russell 1000 Index Return (reflects no deduction for fees, expenses or taxes) Russell Small Cap 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expenses or taxes) ICE BofA USD 3-Month Deposit Offered Rate Constant Maturity Index Return (reflects no deductions for fees, expenses or taxes) Bloomberg U.S. Aggregate Bond Index Return (reflects no deduction for fees, expenses or taxes) ICE BofA U.S. High Yield Constrained Index Return (reflects no deduction for fees, expenses or taxes) The Fund’s 70/30 Blended Benchmark Return (reflects no deduction for fees, expenses or taxes) Bloomberg Long A+ U.S. Credit Index Return (reflects no deductions for fees, expenses or taxes) Bloomberg Short U.S. Treasury 9‑12 Month Index Return (reflects no deduction for fees, expenses or taxes) Bloomberg Global Aggregate Index (USD) Return (reflects no deduction for fees, expenses or taxes) The Fund’s Blended Benchmark Return (reflects no deduction for fees, expenses or taxes) Bloomberg 1‑5 Year U.S. TIPS Index Return (reflects no deduction for fees, expenses or taxes) ICE BofA 1‑3 Year US Treasury Index Return (reflects no deduction for fees, 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