The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE
OMB APPROVAL
OMB Number: 3235-0006
Estimated average burden
hours per response: 23.8
COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
Alexandria COM 015271109 3,461 31,150 SH   SOLE   7,740 0 23,410
Align Technology COM 016255101 4,181 43,500 SH   SOLE   9,260 0 34,240
Allete Inc COM NEW 018522300 784 12,220 SH   SOLE   1,100 0 11,120
Alphabet Inc Cl A CAP STK CL A 02079K305 2,476 3,125 SH   SOLE   1,440 0 1,685
Alphabet Inc Cl C CAP STK CL C 02079K107 505 655 SH   SOLE   410 0 245
Am. Water Works COM 030420103 3,118 43,098 SH   SOLE   8,000 0 35,098
American Tower Corp COM 03027X100 7,316 69,233 SH   SOLE   17,490 0 51,743
Ansys COM 03662Q105 6,160 66,610 SH   SOLE   11,380 0 55,230
Avangrid Inc COM 05351W103 3,656 96,536 SH   SOLE   23,396 0 73,140
Black Hills Corp COM 092113109 1,938 31,610 SH   SOLE   4,000 0 27,610
Blue Bird Crp. COM 095306106 665 43,050 SH   SOLE   6,550 0 36,500
BP SPONSORED ADR 055622104 275 7,377 SH   SOLE   0 0 7,377
Brkfield Rnwble Egy PARTNERSHIP UNIT G16258108 1,855 62,460 SH   SOLE   16,300 0 46,160
Cavco Industries COM 149568107 1,187 11,895 SH   SOLE   890 0 11,005
Celgene COM 151020104 2,553 22,060 SH   SOLE   5,580 0 16,480
Cintas Corp COM 172908105 547 4,740 SH   SOLE   1,030 0 3,710
City Office REIT COM 178587101 633 48,130 SH   SOLE   7,800 0 40,330
CMS Energy Corp COM 125896100 991 23,830 SH   SOLE   7,280 0 16,550
Comm Sales/Leasing COM 20341J104 1,965 77,367 SH   SOLE   13,267 0 64,100
Concho Resources COM 20605P101 298 2,250 SH   SOLE   2,000 0 250
Core Laboratories COM N22717107 1,589 13,240 SH   SOLE   2,440 0 10,800
Coresite Realty COM 21870Q105 8,927 112,473 SH   SOLE   20,560 0 91,913
Corp. Office Properties COM SH BEN INT 22002T702 1,069 34,250 SH   SOLE   600 0 33,650
Costco COM 22160K105 3,370 21,053 SH   SOLE   6,690 0 14,363
Crown Castle Intl Corp COM 22822V101 606 6,990 SH   SOLE   350 0 6,640
CyrusOne Inc. COM 23283R100 4,412 98,640 SH   SOLE   23,800 0 74,840
Digital Globe COM NEW 25389M877 3,906 136,350 SH   SOLE   46,750 0 89,600
Digital Realty COM 253868103 2,601 26,480 SH   SOLE   5,500 0 20,980
Diplomat Pharmacy COM 25456K101 276 21,950 SH   SOLE   2,780 0 19,170
Douglas Dynamics COM 25960R105 1,277 37,953 SH   SOLE   5,200 0 32,753
Enterprise Prod. Ptnrs COM 293792107 4,866 179,975 SH   SOLE   57,500 0 122,475
Entertainment Prprts COM SH BEN INT 26884U109 3,709 51,690 SH   SOLE   11,750 0 39,940
EOG Resources COM 26875P101 927 9,170 SH   SOLE   960 0 8,210
Epam Systems Inc COM 29414B104 1,378 21,440 SH   SOLE   3,150 0 18,290
EQT Midstrm Pntrs UNIT LTD PARTN 26885B100 892 11,640 SH   SOLE   3,570 0 8,070
Equity Commonwealth COM SH BEN INT 294628102 2,223 73,540 SH   SOLE   7,300 0 66,240
Exxon Mobil COM 30231G102 520 5,764 SH   SOLE   1,056 0 4,708
Federal Rlty Invt Trst SH BEN INT NEW 313747206 2,621 18,450 SH   SOLE   4,400 0 14,050
First Majestic Slv Corp COM 32076V103 226 29,727 SH   SOLE   0 0 29,727
FLIR Systems COM 302445101 305 8,430 SH   SOLE   2,500 0 5,930
Gaming & Leisure COM 36467J108 725 23,680 SH   SOLE   2,300 0 21,380
HFF Inc. CL A 40418F108 6,339 209,577 SH   SOLE   1,000 0 208,577
Highwoods Pptys COM 431284108 2,185 42,840 SH   SOLE   5,900 0 36,940
Holly Energy Prtnrs COM UT LTD PTN 435763107 1,612 50,300 SH   SOLE   11,500 0 38,800
Hollyfrontier Corp COM 436106108 2,681 81,850 SH   SOLE   20,900 0 60,950
Hormel Foods COM 440452100 215 6,200 SH   SOLE   900 0 5,300
Idacorp COM 451107106 902 11,199 SH   SOLE   0 0 11,199
IDEXX Labs COM 45168D104 3,289 28,050 SH   SOLE   7,390 0 20,660
Kirby Corporation COM 497266106 1,057 15,895 SH   SOLE   5,050 0 10,845
Ligand Pharma COM NEW 53220K504 563 5,550 SH   SOLE   40 0 5,510
LKQ Corp COM 501889208 2,912 95,040 SH   SOLE   21,420 0 73,620
Lowe's Companies COM 548661107 209 2,940 SH   SOLE   0 0 2,940
LTC Properties COM 502175102 1,528 32,530 SH   SOLE   7,600 0 24,930
Magellan Midstream COM UNIT RP LP 559080106 9,622 127,233 SH   SOLE   36,650 0 90,583
Main Street Capital COM 56035L104 6,025 163,862 SH   SOLE   76,685 0 87,177
Matador Resources Co COM 576485205 2,774 107,710 SH   SOLE   22,900 0 84,810
Mid-Am. Apt. Cmnty's COM 59522J103 2,659 27,160 SH   SOLE   6,600 0 20,560
Middleby Corp COM 596278101 6,053 46,994 SH   SOLE   17,024 0 29,970
Monarch Casino COM 609027107 2,238 86,820 SH   SOLE   15,200 0 71,620
National Instruments COM 636518102 5,292 171,720 SH   SOLE   37,890 0 133,830
Newfield Exploration Co COM 651290108 1,510 37,300 SH   SOLE   6,050 0 31,250
NextEra Energy COM 65339F101 4,007 33,544 SH   SOLE   7,325 0 26,219
NGL Energy Prtnrs COM UNIT REPST 62913M107 209 9,998 SH   SOLE   0 0 9,998
Northwestern Corp COM NEW 668074305 2,122 37,320 SH   SOLE   7,700 0 29,620
Omega Healthcare COM 681936100 599 19,190 SH   SOLE   10,200 0 8,990
Oneok Inc. COM 682680103 624 10,870 SH   SOLE   0 0 10,870
ONEOK Prtnrs UNIT LTD PARTN 68268N103 928 21,580 SH   SOLE   3,200 0 18,380
Orbcomm Inc COM 68555P100 757 91,650 SH   SOLE   9,300 0 82,350
Orchids Paper COM 68572N104 1,733 66,220 SH   SOLE   6,800 0 59,420
Ormat Tech COM 686688102 4,262 79,490 SH   SOLE   21,000 0 58,490
Pembina Pipeline COM 706327103 465 14,870 SH   SOLE   400 0 14,470
Physcns Rlty Trst COM 71943U104 545 28,750 SH   SOLE   6,000 0 22,750
Plains All American PL UNIT LTD PARTN 726503105 6,184 191,542 SH   SOLE   75,168 0 116,374
Plains GP Holdings SHS A REP LTPN 72651A108 3,255 93,860 SH   SOLE   9,781 0 84,079
Retail Opportunity COM 76131N101 4,160 196,899 SH   SOLE   41,180 0 155,719
Rexford Ind Realty COM 76169C100 1,300 56,100 SH   SOLE   7,500 0 48,600
Rsp Permian Inc COM 74978Q105 257 5,760 SH   SOLE   900 0 4,860
SBA Comm Corp COM 78410G104 1,493 14,465 SH   SOLE   1,260 0 13,205
Silver Spring COM 82817Q103 803 60,350 SH   SOLE   13,150 0 47,200
Stag Industrial COM 85254J102 5,030 210,750 SH   SOLE   42,430 0 168,320
Starbucks Corp COM 855244109 1,199 21,610 SH   SOLE   740 0 20,870
Sun Communities COM 866674104 1,657 21,630 SH   SOLE   8,200 0 13,430
Tallgrass GP SHS CL A 874696107 1,129 42,160 SH   SOLE   5,350 0 36,810
Tallgrass LP COM UNIT 874697105 1,100 23,200 SH   SOLE   5,550 0 17,650
Tyler Technologies COM 902252105 421 2,950 SH   SOLE   1,550 0 1,400
Universal Elect COM 913483103 815 12,630 SH   SOLE   1,900 0 10,730
US Silica Holdings Inc. COM 90346E103 1,092 19,270 SH   SOLE   6,740 0 12,530
Vascular Solutions COM 92231M109 407 7,270 SH   SOLE   2,620 0 4,650
Ventas COM 92276F100 1,023 16,370 SH   SOLE   7,090 0 9,280
Verisk Analytics COM 92345Y106 2,443 30,100 SH   SOLE   8,240 0 21,860
Wabtec COM 929740108 5,658 68,160 SH   SOLE   19,010 0 49,150
Waste Connections Inc COM 94106B101 5,590 71,130 SH   SOLE   13,600 0 57,530
Western Gas GP COMUNT LTD PT 95825R103 298 7,050 SH   SOLE   2,500 0 4,550
Western Gas Prtnrs COM UNIT LP IN 958254104 649 11,060 SH   SOLE   2,000 0 9,060
World Point Terminals UNIT REP LTD PT 98159G107 225 13,600 SH   SOLE   2,400 0 11,200
XPO Logistics Inc COM 983793100 1,086 25,170 SH   SOLE   5,000 0 20,170
Zoetis Inc CL A 98978V103 4,401 82,220 SH   SOLE   23,900 0 58,320