SCHEDULE OF INVESTMENTS (Unaudited) June 30, 2017

ENERGY FUND

SHARES VALUE

COMMON STOCKS† - 99.2%

OIL & GAS - 70.8% Exxon Mobil Corp. 12,604 $ 1,017,522 Chevron Corp. 7,389 770,894 EOG Resources, Inc. 4,620 418,202 ConocoPhillips 9,168 403,025 Occidental Corp. 6,388 382,450 4,444 367,474 Valero Energy Corp. 4,555 307,280 Pioneer Natural Resources Co. 1,875 299,213 Anadarko Petroleum Corp. 6,472 293,440 Marathon Petroleum Corp. 5,501 287,867 Concho Resources, Inc.* 2,104 255,699 Petroleo Brasileiro S.A. ADR* 30,986 247,578 Corp. 7,559 241,661 Apache Corp. 4,976 238,500 BP plc ADR 6,345 219,854 Hess Corp. 4,958 217,507 Continental Resources, Inc.* 6,388 206,524 , Inc. 7,060 199,798 Cabot Oil & Gas Corp. — Class A 7,752 194,420 Parsley Energy, Inc. — Class A* 6,570 182,318 Tesoro Corp. 1,918 179,507 Cimarex Energy Co. 1,904 178,995 Corp. 15,099 178,923 Equities Corp. 3,016 176,707 Diamondback Energy, Inc.* 1,982 176,021 plc — Class A ADR 3,138 166,910 Rice Energy, Inc.* 5,750 153,123 Ltd.* 18,552 152,683 RSP Permian, Inc.* 4,310 139,084 Newfield Exploration Co.* 4,853 138,116 Antero Resources Corp.* 6,390 138,088 Encana Corp. 15,644 137,667 Helmerich & Payne, Inc.1 2,500 135,850 Range Resources Corp. 5,825 134,965 Canadian Natural Resources Ltd. 4,574 131,914 , Inc. 4,370 127,604 HollyFrontier Corp. 4,575 125,675 Energen Corp.* 2,499 123,376 WPX Energy, Inc.* 12,676 122,450 Murphy Oil Corp. 4,740 121,486 Patterson-UTI Energy, Inc. 5,941 119,949 Chesapeake Energy Corp.*,1 24,076 119,658 Centennial Resource Development, Inc. — Class A*,1 6,910 109,316 Gulfport Energy Corp.* 6,841 100,905 Southwestern Energy Co.* 16,221 98,624 PDC Energy, Inc.* 2,278 98,205 QEP Resources, Inc.* 9,544 96,394 Ltd.* 14,730 94,419 Ensco plc — Class A 18,168 93,747 Laredo Petroleum, Inc.* 8,894 93,565 Callon Petroleum Co.* 8,550 90,716 Extraction Oil & Gas, Inc.*,1 6,710 90,250 Whiting Petroleum Corp.*,1 16,087 88,639 PBF Energy, Inc. — Class A1 3,945 87,816 Ltd. 10,591 86,211 Matador Resources Co.* 3,980 85,053 Oasis Petroleum, Inc.* 10,191 82,038 SM Energy Co. 4,848 80,137 Delek US Holdings, Inc. 2,740 72,446 SRC Energy, Inc.*,1 10,097 67,953 Diamond , Inc.*,1 6,107 66,139 Carrizo Oil & Gas, Inc.* 3,671 63,949 Rowan Companies plc — Class A* 5,795 59,341 Statoil ASA ADR 2,980 49,259 Resolute Energy Corp.* 1,621 48,257 Atwood Oceanics, Inc.* 5,620 45,803 Sanchez Energy Corp.*,1 5,900 42,362 California Resources Corp.*,1 3,751 32,071 Total Oil & Gas 11,953,592

OIL & GAS SERVICES - 13.6% Ltd. 8,118 534,489 Co. 7,944 339,288 , Inc. 4,802 261,757 National Oilwell Varco, Inc. 5,996 197,508 TechnipFMC plc* 5,473 148,866 RPC, Inc.1 5,608 113,338 McDermott International, Inc.* 11,710 83,961 Oceaneering International, Inc. 3,561 81,333 Keane Group, Inc.*,1 4,780 76,480 Core Laboratories N.V. 741 75,041 Dril-Quip, Inc.* 1,527 74,518 Superior Energy Services, Inc.* 6,975 72,749 Forum Energy Technologies, Inc.* 4,270 66,612 Oil States International, Inc.* 2,436 66,137 Basic Energy Services, Inc.* 2,095 52,166 Helix Energy Solutions Group, Inc.* 9,167 51,702 Total Oil & Gas Services 2,295,945

PIPELINES - 10.3% Kinder Morgan, Inc. 19,069 365,362 Williams Companies, Inc. 9,622 291,354 Cheniere Energy, Inc.* 4,109 200,149 ONEOK, Inc. 3,699 192,940 Targa Resources Corp. 4,140 187,128 , Inc. 4,294 170,944 Plains GP Holdings, LP — Class A 6,521 170,589 SemGroup Corp. — Class A 3,243 87,561 TransCanada Corp. 1,550 73,889 Total Pipelines 1,739,916

COAL - 1.6% CONSOL Energy, Inc.* 6,986 104,370 Peabody Energy Corp.*,1 3,610 88,265 Arch Coal, Inc. — Class A 1,140 77,862 Total Coal 270,497 SCHEDULE OF INVESTMENTS (Unaudited)(concluded) June 30, 2017

ENERGY FUND

SHARES VALUE

MINING - 0.9% US Silica Holdings, Inc. 2,825 $ 100,259 Fairmount Santrol Holdings, Inc.*,1 14,573 56,835 Total Mining 157,094

METAL FABRICATE & HARDWARE - 0.6% Tenaris S.A. ADR 3,260 101,516

RETAIL - 0.6% World Fuel Services Corp. 2,460 94,587

TRANSPORTATION - 0.5% Golar LNG Ltd. 3,592 79,922

ENERGY-ALTERNATE SOURCES - 0.3% Green Plains, Inc. 2,383 48,971

Total Common Stocks (Cost $10,125,657) 16,742,040

FACE AMOUNT

REPURCHASE AGREEMENTS††,2 - 0.6% HSBC Securities, Inc. issued 06/30/17 at 0.99% due 07/03/17 $ 71,939 71,939 Bank of America Merrill Lynch issued 06/30/17 at 1.08% due 07/03/17 26,640 26,640 Total Repurchase Agreements (Cost $98,579) 98,579

SHARES

SECURITIES LENDING COLLATERAL†,3 - 5.2% First American Government Obligations Fund — Class Z, 0.84%4 880,204 880,204 Total Securities Lending Collateral (Cost $880,204) 880,204

Total Investments - 105.0% (Cost $11,104,440) $ 17,720,823 Other Assets & Liabilities, net - (5.0)% (840,146) Total Net Assets - 100.0% $ 16,880,677

* Non-income producing security. † Value determined based on Level 1 inputs. †† Value determined based on Level 2 inputs. 1 All or portion of this security is on loan at June 30, 2017. 2 Repurchase Agreements. 3 Securities lending collateral. 4 Rate indicated is the 7 day yield as of June 30, 2017. ADR — American Depositary Receipt plc — Public Limited Company