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You can find additional information about the Fund at <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">www.sitfunds.com/documents</span>. You can also request this information by contacting us at 1-800-332-5580.  1-800-332-5580 82 0.0080 Sit U.S. Government Securities Fund - Class S 10000 10000 10000 10002 10044 9933 10078 10165 9919 10411 10620 10295 10958 11569 11214 11006 11651 11079 10769 11168 10618 10566 10633 10456 10740 10814 10628 11317 11342 11197 11787 11835 11642 0.0416 0.0138 0.0166 0.0435 0.0031 0.0170 0.0398 0.0100 0.0153 196960227 159 0.1251 408661 <p style="text-align: left; box-sizing: border-box; color: rgb(0, 0, 0); display: block; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align-last: auto; white-space-collapse: preserve-breaks;">There were no material changes to the Fund during the 12-month period ended March 31, 2026.</p> 2026-03-31 Class S Sit U.S. Government Securities Fund Annual Shareholder Report Class Y Sit U.S. Government Securities Fund Annual Shareholder Report This annual shareholder report contains important information about Sit U.S. Government Securities Fund for the period of April 1, 2025 to March 31, 2026. You can find additional information about the Fund at <span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left; text-align-last: auto; white-space-collapse: preserve-breaks;">www.sitfunds.com/documents</span>. You can also request this information by contacting us at 1-800-332-5580.  1-800-332-5580 56 0.0055 Sit U.S. Government Securities Fund - Class Y 10101 10192 10141 10320 10315 10518 10395 10388 10391 10196 9957 9959 10025 9481 9808 10216 9641 9969 10783 10112 10502 11260 10552 10920 0.0442 0.0161 0.0192 0.0435 0.0031 0.0086 0.0398 0.0100 0.0142 196960227 159 0.1251 408661 <p style="text-align: left; box-sizing: border-box; color: rgb(0, 0, 0); display: block; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align-last: auto; white-space-collapse: preserve-breaks;">There were no material changes to the Fund during the 12-month period ended March 31, 2026.</p> 2026-03-31 Class Y Sit U.S. Government Securities Fund Annual Shareholder Report