system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
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the Imbalance is the result of receipts at the Point(s) of Receipt exceeding the delivered (or scheduled, as applicable) quantity of Gas for Customer's account at the Point(s) of Delivery, it is a "Positive Imbalance". If the Imbalance is a result of receipts at the Point(s) of Receipt being lower than the delivered quantity of Gas for Customer's account at the Point(s) of Delivery, it is a "Negative Imbalance". Imbalances will be cashed out on a Monthly basis. 8 Source: PENNTEX MIDSTREAM PARTNERS, LP, S-1/A, 4/16/2015 Cash Out. The cash-out settlement price will be the monthly arithmetical average of the prices ("Cash-out Price") as posted in Gas Daily's Daily Price Survey during the Month under the heading "Texas Gas Transmission Corp.," under the column labeled "Index" corresponding to the row labeled "Zone 1." Transporter will pay Customer an amount that is the product of the Positive Imbalance each Month, if any, and the Cash-out Price. Customer will pay Transporter an amount that is the product of the Negative Imbalance each Month, if any, and the Cash-out Price. If the actual monthly volume varies by more than five percent (5%) from the delivered volumes for the Month, then the Cash-out Price will be adjusted as follows: 1. For Negative Imbalances, the Cash-out Price will be increased by the percentage variance, rounded up to the nearest whole percentage point, between the Point(s) of Delivery volumes and the adjusted Point(s) of Receipt volumes. (i.e., if the adjusted receipt volume from Customer is 7% less than the Point(s) of Delivery volume, then the Index Price will be increased by 7%), however in no event shall the Cash-Out Price be increased more than 10%; and 2. For Positive Imbalances, the Cash-out Price will be decreased by the percentage variance, rounded up to the nearest whole percentage point, between the Point(s) of Delivery volumes and the adjusted Point(s) of Receipt volumes. (i.e., if the adjusted receipt volume from Customer is 7% greater than the Point(s) of Delivery volume, then the Index Price will be increased by 7%), however in no event shall the Cash-Out Price be increased more than 10%. Article V. Curtailment If the quantity of Customer Gas and all other Gas available for delivery into the Transportation System exceeds the capacity of the Transportation System at any point, then Transporter shall interrupt or curtail receipts of Customer Gas with respect to the affected point(s) only in accordance with the following: (a) First, Transporter shall curtail all Interruptible Service Gas prior to curtailing Firm Service Gas. In the event Transporter curtails some, but not all, Interruptible Service Gas on a particular Day, Transporter shall allocate the capacity of the Transportation System available for Interruptible Service Gas at the affected points on a pro rata basis based upon Customer's last confirmed nomination of Interruptible Service Gas hereunder and the last confirmed nominations of Interruptible Service Gas from all other shippers on the Transportation System prior to the event causing the curtailment. (b) Second, if additional curtailments are required beyond those described in the immediately preceding clause (a), Transporter shall curtail Firm Service Gas. In the event Transporter curtails some, but not all, Firm Service Gas on a particular Day, Transporter shall allocate the capacity of the Transportation System at the affected point(s) on a pro rata basis based upon Customer's last confirmed nomination of Firm Service Gas hereunder and the last confirmed nominations of Firm Service Gas from all other shippers on the Transportation System prior to the event causing the curtailment. Transporter shall provide Customer notice of any interruption or curtailment of the receipt of Customer Gas into the Transportation System as is reasonable under the circumstances. Article VI. Measurement & Testing The construction, ownership, installation, operation and maintenance of each Measurement Facility that is owned by a Person other than Transporter shall be governed by an interconnect agreement between Transporter and such Person. Each other Measurement Facility shall be constructed, installed, owned, operated and maintained by Transporter. 9 Source: PENNTEX MIDSTREAM PARTNERS, LP, S-1/A, 4/16/2015 Article VII. Gas Quality Notwithstanding anything to the contrary in this Agreement, Customer Gas received at a Point of Receipt from one of the Plants shall be deemed to be in compliance with the applicable Gas quality specifications of the Transportation System. Article VIII. Fees, Billing & Payment Fees. (a) Transportation Fee. For all Customer Gas received by Transporter at a Point of Receipt and delivered to any Point of Delivery, Customer shall pay Transporter a transportation fee of
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Extract the exact clause related to "Parties" from the excerpt above.

assistant: Customer