Our customer base is highly concentrated, with our top five customers accounting for approximately 56.4% and 65.5% of total contract revenues during the three months ended April 27, 2024 and April 29, 2023, respectively. Customers whose contract revenues exceeded 10% of total contract revenues during the three months ended April 27, 2024 or April 29, 2023, as well as total contract revenues from all other customers combined, were as follows (dollars in millions):


	For the Three Months Ended
	April 27, 2024			April 29, 2023
	Amount		% of Total	Amount		% of Total
AT&T Inc.	$	215.5	18.9%	$	224.4	21.5%
Lumen Technologies	156.8		13.7	136.4		13.0
Comcast Corporation	105.0		9.2	120.6		11.5
Total other customers combined	665.1		58.2	564.1		54.0
Total contract revenues	$	1,142.4	100.0%	$	1,045.5	100.0%

See Note 6, Accounts Receivable, Contract Assets, and Contract Liabilities, for information on our customer credit concentration and collectability of trade accounts receivable and contract assets.

Total contract revenues by customer type during the three months ended April 27, 2024 and April 29, 2023 were as follows (dollars in millions):


	For the Three Months Ended
	April 27, 2024			April 29, 2023
	Amount		% of Total	Amount		% of Total
Telecommunications	$	1,026.8	89.9%	$	938.2	89.7%
Underground facility locating	81.0		7.1	73.0		7.0
Electrical and gas utilities and other	34.6		3.0	34.3		3.3
Total contract revenues	$	1,142.4	100.0%	$	1,045.5	100.0%

Master service agreements and other contractual agreements with customers contain customer-specified service requirements, such as discrete pricing for individual tasks. In most cases, our customers are not contractually committed to procure specific volumes of services under these agreements.

Services are generally performed pursuant to these agreements in accordance with individual work orders. An individual work order generally is completed within one year. As a result, our remaining performance obligations under the work orders not yet completed is not meaningful in relation to our overall revenue at any given point in time. We apply the practical expedient in Accounting Standards Codification Topic 606, Revenue from Contracts with Customers, and do not disclose information about remaining performance obligations that have original expected durations of one year or less.