Years Ended December 31,
2019
2018
Termination of long distance minutes
$696.1
$793.6
Total revenue from contracts with customers
696.1
793.6
Other revenue
—
—
Total Telecommunications segment revenue
$696.1
$793.6

text: Telecommunications Segment
text: ICS operates an extensive network of direct routes and offers premium voice communication services for carrying a mix of business, residential and carrier long-distance traffic, data and transit traffic. Customers may have a bilateral relationship with ICS, meaning they have both a customer and vendor relationship with ICS. In these cases, ICS sells the customer access to the ICS supplier routes but also purchases access to the customer’s supplier routes.
text: Net revenue is derived from the long-distance data and transit traffic. Net revenue is earned based on the number of minutes during a call multiplied by the price per minute, and is recorded upon completion of a call. Completed calls are billable activity while incomplete calls are non-billable. Incomplete calls may occur as a result of technical issues or because the customer’s credit limit was exceeded and thus the customer routing of traffic was prevented.
text: Revenue for a period is calculated from information received through ICS’s billing software, such as minutes and market rates. Customized billing software has been implemented to track the information from the switch and analyze the call detail records against stored detailed information about revenue rates. This software provides ICS with the ability to perform a timely and accurate analysis of revenue earned in a period.
text: ICS evaluates gross versus net revenue recognition for each of its contractual arrangements by assessing indicators of control and significant influence to determine whether the ICS acts as a principal (i.e. gross recognition) or an agent (i.e. net recognition). ICS has determined that it acts as a principal for all of its performance obligations in connection with all revenue earned. Net revenue represents gross revenue, net of allowance for doubtful accounts receivable, service credits and service adjustments. Cost of revenue includes network costs that consist of access, transport and termination costs. The majority of ICS’s cost of revenue is variable, primarily based upon minutes of use, with transmission and termination costs being the most significant expense.
text: Disaggregation of Revenues ICS's revenues are predominantly derived from wholesale of international long distance minutes (in millions):

Questions:
question: How is the net revenue derived?
answer: derived from the long-distance data and transit traffic.
question: How is the revenue for a period calculated?
answer: from information received through ICS’s billing software, such as minutes and market rates.
question: What was the termination of long distance minutes in 2019?
answer: $696.1
scale: million
question: What is the change in the Termination of long distance minutes from 2018 to 2019?
answer: -97.5
derivation: 696.1 - 793.6
scale: million
question: What is the average Total revenue from contracts with customers for 2018 and 2019?
answer: 744.85
derivation: (696.1 + 793.6) / 2
scale: million
question: What is the percentage change in the Total Telecommunications segment revenue from 2018 to 2019?
answer: -12.29
derivation: 696.1 / 793.6 - 1
scale: percent