Pioneer Municipal High Income Trust - Semi-Annual Report (management company) (NSAR-A)

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011 C020001 MA 011 C030001 02109 011 A000002 UBS WARBURG 011 B000002 8-022651 011 C010002 STAMFORD 011 C020002 CT 011 C030002 06901 011 A000003 RBC CAPITAL MARKETS 011 B000003 8-045411 011 C010003 MINNEAPOLIS 011 C020003 MN 011 C030003 55402 011 C040003 4422 011 A000004 ADVEST, INC. 011 B000004 8-21409 011 C010004 HARTFORD 011 C020004 CT 011 C030004 06103 011 A000005 JANNEY MONTGOMERY SCOTT, LLC 011 B000005 8-462 011 C010005 PHILADELPHIA 011 C020005 PA 011 C030005 19103 011 C040005 1675 011 A000006 MCDONALD INVESTMENTS, INC. 011 B000006 8-30177 011 C010006 CLEVELAND 011 C020006 OH 011 C030006 44114 011 C040006 2603 011 A000007 STIFEL, NICOLAUS & COMPANY, INC. 011 B000007 8-001447 011 C010007 ST. LOUIS 011 C020007 MO 011 C030007 63102 012 A000001 PIONEER INVESTMENT MGT. SHAREHOLDER SERVICES 012 B000001 85-00000 012 C010001 BOSTON 012 C020001 MA 012 C030001 02109 012 A000002 AMERICAN STOCK TRANSFER & TRUST CO. (COMMON) 012 B000002 85-00000 012 C010002 BROOKLYN 012 C020002 NY 012 C030002 11219 012 A000003 DEUTSCHE BANK TRUST COMPANY AMERICAS (PREF.) 012 B000003 85-00000 012 C010003 NEW YORK 012 C020003 NY 012 C030003 10005 013 A000001 ERNST & YOUNG LLP

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013 B010001 BOSTON 013 B020001 MA 013 B030001 02116 013 B040001 5072 015 A000001 BROWN BROTHERS HARRIMAN & CO. 015 B000001 C 015 C010001 BOSTON 015 C020001 MA 015 C030001 02109 015 E010001 X 018 000000 Y 019 A000000 Y 019 B000000 81 019 C000000 PIONEERFDS 020 C000001 0 020 C000002 0 020 C000003 0 020 C000004 0 020 C000005 0 020 C000006 0 020 C000007 0 020 C000008 0 020 C000009 0 020 C000010 0 021 000000 0 022 A000001 BLACKROCK, INC. 022 B000001 13-3806694 022 C000001 206047 022 D000001 0 022 A000002 LEHMAN BROTHERS, INC. 022 B000002 13-2518466 022 C000002 9697 022 D000002 3055 022 A000003 CORBY CAPITAL MARKETS, INC. 022 B000003 52-1037969 022 C000003 0 022 D000003 10815 022 A000004 UBS SECURITIES, LLC 022 B000004 13-3873456 022 C000004 4328 022 D000004 5023 022 A000005 PIPER JAFFRAY & CO. 022 B000005 41-0953246 022 C000005 7859 022 D000005 1071 022 A000006 HERBERT J. SIMS & CO., INC. 022 B000006 13-5213180 022 C000006 7019 022 D000006 0 022 A000007 FIRST TRYON SECURITIES, LLC 022 B000007 56-1986792

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088 D000000 Y SIGNATURE MARY KELLERMANN TITLE ACCOUNTING MANAGER