Exhibit 99.1

GRAPHIC

February 23,
2018

Bank
of New York Mellon Trust Company, N.A.
as Trustee of VOC Energy Trust
Attn: Mike Ulrich
919 Congress Avenue
Austin, Texas 78701



Re:

Evaluation Summary

Pursuant to the Guidelines of theVOC Energy Trust Net Profits Interests

Securities and Exchange Commission forTotal Proved Reserves

Reporting Corporate Reserves andCertain Properties in Kansas & Texas

Future Net RevenueAs of December 31, 2017




As
requested, this report was prepared on February 23, 2018 forVOC Energy Trust("Trust") for the purpose of
submitting our estimates of total proved reserves and forecasts of economics attributable to the Trust term net profits interests. We evaluated 100% of the Trust reserves, which are made up of oil and
gas properties in Kansas and Texas owned by VOC Brazos Energy Partners, L.P. and VOC Kansas Energy Partners, LLC ("Companies"). This evaluation, effective December 31, 2017, was
prepared using constant prices and costs, and conforms to Item 1202(a)(8) of Regulation S-K and other rules of theSecurities and Exchange
Commission(SEC). A composite summary of the proved reserves is presented below.



Proved
Developed
Producing

Proved
Developed
Non-Producing

Proved
Undeveloped

Total
ProvedNet ReservesOil

MBBL


4,133.2


46.3


821.0


5,000.6Gas

MMCF


1,650.0


0.0


483.8


2,133.7RevenueOil

M$


197,195.1


2,121.3


40,616.7


239,933.0Gas

M$


4,892.4


0.0


1,805.4


6,697.8Severance Taxes

M$


4,973.9


54.4


1,847.3


6,875.6Ad Valorem Taxes

M$


5,118.4


88.8


1,398.4


6,605.6Operating Expenses

M$


91,462.0


0.0


2,624.1


94,086.1Workover Expenses

M$


10,371.3


0.0


0.0


10,371.3COPAS

M$


12,972.2


0.0


307.0


13,279.2Investments

M$


0.0


403.8


21,966.6


22,370.480% NPI Net Cash Flow (BFIT)

M$


61,751.9


1,259.4


11,422.9


74,434.280% NPI Disc. @ 10%

M$


40,280.6


809.9


4,151.6


45,242.0(Present Worth)


Proved
Developed reserves are the summation of the Proved Developed Producing and Proved Developed Non-Producing reserve estimates. Proved Developed reserves were estimated at
4,179.5 Mbbl oil and 1,650.0 MMcf gas (or 4,454.5 MBOE). Of the Proved Developed reserves, 4,408.2 MBOE were attributed to producing zones in existing wells and 46.3 MBOE were
attributed to zones in existing wells not producing.

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Future revenuewas calculated prior to deducting state production taxes and ad valorem taxes; however,future net
cash flowwas calculated after deducting these taxes, future capital costs and operating expenses, but before federal income taxes.Future net cash
flowhas been discounted at an annual rate of ten (10) percent, in accordance with SEC guidelines, to determinenet present
worth. Present worth indicates the time value of money and should not be construed as being fair market value.

The
oil reserves include oil and condensate. Oil volumes are expressed in barrels (42 U.S. gallons). Gas volumes are expressed in thousands of standard cubic feet (Mcf) at contract
temperature and pressure base. BOE (barrels of oil equivalent) is expressed as oil and NGL volumes in barrels plus gas volumes in Mcf divided by six (6) to convert to barrels. Our estimates
include proved reserves only. Neither probable or possible reserves, nor interest in acreage beyond the location of proven reserves have been estimated.

Net Profits Calculations

The net profits interests entitle the Trust to receive 80% of the net proceeds from the sale of hydrocarbon production within the Company
underlying properties. The net profits interests will terminate on the later to occur (1) December 31, 2030, or (2) the time when 10.6 million barrels of oil equivalent
("MMBOE") have been produced from the underlying properties and sold, and the trust will soon thereafter wind up its affairs and terminate. For this report, it was estimated that the Trust would
terminate December 31, 2030 based on the calculation that 10.6 MMBOE would be produced from the underlying properties and sold (which amount is the equivalent of 8.5 MMBOE in respect of the
trust's right to receive 80% of the net proceeds from the underlying properties pursuant to the net profits interest) by September 30, 2030. The cash flow tables in this report reflect the
termination date of December 31, 2030.

Hydrocarbon Pricing

The base SEC oil and gas prices calculated for December 31, 2017 were $51.34/bbl and $2.964/MMBTU, respectively. As specified by the SEC,
a company must use a 12-month average price, calculated as the unweighted arithmetic average of the first-day-of-the-month price for each month within the 12-month period prior to the end of the
reporting period. The base oil price is based upon WTI-Cushing spot prices (Bloomberg) during 2017 and the base gas price is based upon Henry Hub spot prices (Platts Gas Daily) during 2017.

Oil
price differentials were forecast at $5.50 per BBL for all VOC KEP (Kansas) properties. For Texas properties, oil price differentials were applied at
$1.00 per BBL and $2.15 per BBL for the Kurten (Woodbine) Field wells and Sand Flat Unit wells, respectively. Oil price differentials for all other wells in Texas
were applied at $1.00 per BBL. Gas price differentials varied by property as provided. These base price differentials may include local basis differentials, transportation, gas
shrinkage, gas heating value (BTU content) and/or crude quality and gravity corrections. After these adjustments, the net realized prices for the SEC price case over the trust life of the proved
properties was estimated to be $47.981
per BBL for oil and $3.139 per MCF for gas. All economic factors were held constant in accordance with SEC guidelines.

Economic Parameters

Ownership was accepted as furnished and has not been independently confirmed. Oil and gas price differentials, lease operating expenses (LOE),
workover expenses, overhead expenses and investments were calculated and prepared by the Companies and reviewed by CG&A for accuracy and completeness. LOE (column 22) and overhead (COPAS,
column 26) were determined at the well level using averages determined from historical lease operating statements. Workover Expenses (column 25) were applied to cover the annual
costs for recurring well work and wellbore abandonment. All economic parameters, including expenses and investments, were held constant (not escalated) throughout the life of these properties.

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For
Kansas properties, severance taxes were applied at 4.33 percent of revenue until exemption levels were forecasted to be reached. The severance tax rate was dropped to zero
(0) when a rate of six (6) BBL/day per well was reached, or when gross gas production value reached $87/day per gas well. Severance taxes were forecasted at 4.6 percent of
oil revenue and 7.5 percent of gas revenue for properties in Texas. Ad valorem taxes for Kansas properties were applied at 6.0 percent of revenue, but dropped to 2.0 percent as
properties qualified for the tax exemption. Kansas oil and gas conservation taxes were included within the severance tax estimates shown herein. Ad valorem taxes were applied at 3.29 percent of
revenue (after severance taxes) for Texas properties.

SEC Conformance and Regulations

The reserve classifications and the economic considerations used herein for the SEC pricing scenario conform to the criteria of the SEC as
defined in pages three (3) and four (4) of the Appendix. The reserves and economics are predicated on regulatory agency classifications, rules, policies, laws, taxes and royalties
currently in effect except as noted herein. The possible effects of changes in legislation or other Federal or State restrictive actions which could affect the reserves and
economics have not been considered. However, we do not anticipate nor are we aware of any legislative changes or restrictive regulatory actions that may impact the recovery of reserves.

This
evaluation includes 18 proved undeveloped ("PUD") locations in various fields throughout Kansas and Texas. Fourteen (14) locations are commercial based on SEC pricing. Each
of these drilling locations proposed as part of the Companies' development plans conforms to the proved undeveloped standards as set forth by the SEC. In our opinion, the Companies have indicated they
have intent to complete this development plan within the next five (5) years. Furthermore, the Companies have demonstrated that they have the proper company staffing, financial backing and
prior development success to ensure this five (5) year development plan will be fully executed.

Reserve Estimation Methods

The methods employed in estimating reserves are described in page two (2) of the Appendix. Reserves for proved developed producing wells
were estimated using production performance methods for the vast majority of properties. Certain new producing properties with very little production history were forecast using a combination of
production performance and analogy to similar production, both of which are considered to provide a relatively high degree of accuracy.

Non-producing
reserve estimates, for both developed and undeveloped properties, were forecast using either volumetric or analogy methods, or a combination of both. These methods provide
a relatively high degree of accuracy for predicting proved developed non-producing and proved undeveloped reserves for the Companies' properties, due to the mature nature of their properties targeted
for development and an abundance of subsurface control data. The assumptions, data, methods and procedures used herein are appropriate for the purpose served by this report.

General Discussion

The estimates and forecasts were based upon interpretations of data furnished by your office and available from our files. To some extent
information from public records has been used to check and/or supplement these data. The basic engineering and geological data were subject to third party reservations and qualifications. Nothing has
come to our attention, however, that would cause us to believe that we are not justified in relying on such data. All estimates represent our best judgment based on the data available at the time of
preparation. Due to inherent uncertainties in future production rates, commodity prices and geologic conditions, it should be realized that the reserve
estimates, the reserves actually recovered, the revenue derived therefrom and the actual cost incurred could be more or less than the estimated amounts.

An
on-site field inspection of the properties has not been performed. The mechanical operation or condition of the wells and their related facilities have not been examined nor have the
wells been tested by Cawley, Gillespie & Associates, Inc. Possible environmental liability related to the properties

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has
not been investigated nor considered. The cost of plugging and the salvage value of equipment at abandonment have been included as part of the workover expenses described previously.

Cawley,
Gillespie & Associates, Inc. is a Texas Registered Engineering Firm (F-693), made up of independent registered professional engineers and geologists that have
provided petroleum consulting services to the oil and gas industry for over 50 years. This evaluation was supervised by W. Todd Brooker, President at Cawley, Gillespie &
Associates, Inc. and a State of Texas Licensed Professional Engineer (License #83462). We do not own an interest in the properties, VOC Brazos Energy Partners, L.P., VOC Kansas Energy
Partners, LLC or VOC Energy Trust and are not employed on a contingent basis. We have used all methods and procedures that we consider necessary under the circumstances to prepare this report.
Our work-papers and related data utilized in the preparation of these estimates are available in our office.



Yours very truly,GRAPHICW. Todd Brooker, P.E. Senior Vice PresidentCAWLEY, GILLESPIE &
ASSOCIATES, INC.Texas Registered Engineering Firm (F-693)

GRAPHIC


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APPENDIX  Methods Employed in the Estimation of Reserves

The four methods customarily employed in the estimation of reserves are (1)production
performance, (2)material balance,
(3)volumetricand (4)analogy.
Most estimates, although based primarily on one method, utilize other methods depending on the nature and extent of the data available and the characteristics of the reservoirs.

Basic
information includes production, pressure, geological and laboratory data. However, a large variation exists in the quality, quantity and types of information available on
individual properties. Operators are generally required by regulatory authorities to file monthly production reports andmaybe required to measure and
report periodically such data as well pressures, gas-oil ratios, well tests, etc. As a general rule, an operator has complete discretion in obtaining and/or making available geological and engineering
data. The resulting lack of uniformity in data renders impossible the application of identical methods to all properties, and may result in significant differences in the accuracy and reliability of
estimates.

A
brief discussion of each method, its basis, data requirements, applicability and generalization as to its relative degree of accuracy follows:

Production performance.This method employs graphical analyses of production data on the premise that all factors which
have controlled the performance to date will continue to control and that historical trends can be extrapolated to predict future performance. The only information required is production history.
Capacity production can usually be analyzed from graphs of rates versus time or cumulative production. This procedure is referred to as "decline curve" analysis. Both capacity and restricted
production can, in some cases, be analyzed from graphs of producing rate relationships of the various production components. Reserve estimates obtained by this method are generally considered to have
a relatively high degree of accuracy with the degree of accuracy increasing as production history accumulates.

Material balance.This method employs the analysis of the relationship of production and pressure performance on the
premise that the reservoir volume and its initial hydrocarbon content are fixed and that this initial hydrocarbon volume and recoveries therefrom can be estimated by analyzing changes in pressure with
respect to production relationships. This method requires reliable pressure and temperature data, production data, fluid analyses and knowledge of the nature of the reservoir. The material balance
method is applicable to all reservoirs, but the time and expense required for its use is dependent on the nature of the reservoir and its fluids. Reserves for depletion type reservoirs can be
estimated from graphs of pressures corrected for compressibility versus cumulative production, requiring only data that are usually available. Estimates for other reservoir types require extensive
data and involve complex calculations most suited to computer models which makes this method generally applicable only to reservoirs where there is economic justification for its use. Reserve
estimates obtained by this method are generally considered to have a degree of accuracy that is directly related to the complexity of the reservoir and the quality and quantity of data available.

Volumetric.This method employs analyses of physical measurements of rock and fluid properties to calculate the volume
of hydrocarbons in-place. The data required are well information sufficient to determine reservoir subsurface datum, thickness, storage volume, fluid content and location. The volumetric method is
most applicable to reservoirs which are not susceptible to analysis by production performance or material balance methods. These are most commonly newly developed and/or no-pressure depleting
reservoirs. The amount of hydrocarbons in-place that can be recovered is not an integral part of the volumetric calculations but is an estimate inferred by other methods and a knowledge of the nature
of the reservoir. Reserve estimates obtained by this method are generally

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considered
to have a low degree of accuracy; but the degree of accuracy can be relatively high where rock quality and subsurface control is good and the nature of the reservoir is uncomplicated.

Analogy.This method, which employs experience and judgment to estimate reserves, is based on observations of similar
situations and includes consideration of theoretical performance. The analogy method is a common approach used for "resource plays," where an abundance of wells with similar production profiles
facilitates the reliable estimation of future reserves with a relatively high degree of accuracy. The analogy method may also be applicable where the data are insufficient or so inconclusive that
reliable reserve estimates cannot be made by other methods. Reserve estimates obtained in this manner are generally considered to have a relatively low degree of accuracy.

Much
of the information used in the estimation of reserves is itself arrived at by the use of estimates. These estimates are subject to continuing change as additional information
becomes available. Reserve estimates which presently appear to be correct may be found to contain substantial errors as time passes and new information is obtained about well and reservoir
performance.

APPENDIX  Reserve Definitions and Classifications

The Securities and Exchange Commission, in SX Reg. 210.4-10 dated November 18, 1981, as amended on September 19, 1989 and
January 1, 2010, requires adherence to the following definitions of oil and gas reserves:

"(22)Proved oil and gas reserves.Proved oil and gas reserves are those quantities of oil and gas, which, by
analysis of geoscience and engineering data, can be estimated with reasonable certainty to be economically produciblefrom a given date forward, from known reservoirs, and under existing
economic conditions, operating methods, and government regulationsprior to the time at which contracts providing the right to operate expire, unless evidence indicates that renewal is
reasonably certain, regardless of whether deterministic or probabilistic methods are used for the estimation. The project to extract the hydrocarbons must have commenced or the operator must be
reasonably certain that it will commence the project within a reasonable time.



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"(6)Developed oil and gas reserves.Developed oil and gas reserves are reserves of any category that can be
expected to be recovered:



"(31)Undeveloped oil and gas reserves.Undeveloped oil and gas reserves are reserves of any category that are
expected to be recovered from new wells on undrilled acreage, or from existing wells where a relatively major expenditure is required for recompletion.



"(18)Probable reserves.Probable reserves are those additional reserves that are less certain to be recovered
than proved reserves but which, together with proved reserves, are as likely as not to be recovered.



"(17)Possible reserves.Possible reserves are those additional reserves that are less certain to be recovered
than probable reserves.

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Instruction 4
of Item 2(b) of Securities and Exchange Commission Regulation S-K was revised January 1, 2010 to state that "a registrant engaged in oil and gas
producing activities shall provide the information
required by Subpart 1200 of Regulation S-K." This is relevant in that Instruction 2 to paragraph (a)(2) states: "The registrant ispermitted, but
not required, to disclose probable or possible reserves pursuant to paragraphs (a)(2)(iv) through (a)(2)(vii) of this Item."

"(26)Reserves.Reserves are estimated remaining quantities of oil and gas and related substances anticipated to
be economically producible, as of a given date, by application of development projects to known accumulations. In addition, there must exist, or there must be a reasonable expectation that there will
exist, the legal right to produce or a revenue interest in the production, installed means of delivering oil and gas or related substances to market, and all permits and financing required to
implement the project.

"Note to paragraph (26):    Reserves should not be assigned to adjacent reservoirs isolated by major, potentially sealing, faults
until those
reservoirs are penetrated and evaluated as economically producible. Reserves should not be assigned to areas that are clearly separated from a known accumulation by a non-productive reservoir
(i.e., absence of reservoir, structurally low reservoir, or negative test results). Such areas may contain prospective resources (i.e., potentially recoverable resources from
undiscovered accumulations)."

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