On a consolidated basis, activity in benefits payable was as follows for the six months ended June 30, 2022 and 2021:


	For the six months ended June 30,
	2022		2021
	(in millions)
Balances, beginning of period	$	8,289	$	8,143



Acquisitions	—		42
Incurred related to:
Current year	39,121		35,164
Prior years	(397)		(719)
Total incurred	38,724		34,445
Paid related to:
Current year	(30,356)		(27,556)
Prior years	(7,007)		(6,589)
Total paid	(37,363)		(34,145)


Balances, end of period	$	9,650	$	8,485

Amounts incurred related to prior periods vary from previously estimated liabilities as the claims ultimately are settled. Negative amounts reported for incurred related to prior years result from claims being ultimately settled for amounts less than originally estimated (favorable development).

Our reserving practice is to consistently recognize the actuarial best estimate of our ultimate liability for claims. Actuarial standards require the use of assumptions based on moderately adverse experience, which generally results in favorable reserve development, or reserves that are considered redundant.

The following discussion provides information about incurred and paid claims development for our Retail and Group and Specialty segments as of June 30, 2022 and 2021, net of reinsurance, and the total estimate of benefits payable for claims incurred but not reported, or IBNR, included within the net incurred claims amounts.

Activity in benefits payable for our Retail segment was as follows for the six months ended June 30, 2022 and 2021:


	For the six months ended June 30,
	2022		2021
	(in millions)
Balances, beginning of period	$	7,675	$	7,428



Acquisitions	—		42
Incurred related to:
Current year	37,299		32,986
Prior years	(367)		(619)
Total incurred	36,932		32,367
Paid related to:
Current year	(29,061)		(25,953)
Prior years	(6,459)		(5,990)
Total paid	(35,520)		(31,943)


Balances, end of period	$	9,087	$	7,894

At June 30, 2022, benefits payable for our Retail segment included IBNR of approximately $5.5 billion, primarily associated with claims incurred in 2022.

Activity in benefits payable for our Group and Specialty segment was as follows for the six months ended June 30, 2022 and 2021:


	For the six months ended June 30,
	2022		2021
	(in millions)
Balances, beginning of period	$	614	$	715




Incurred related to:
Current year	2,121		2,492
Prior years	(30)		(100)
Total incurred	2,091		2,392
Paid related to:
Current year	(1,594)		(1,917)
Prior years	(548)		(599)
Total paid	(2,142)		(2,516)


Balances, end of period	$	563	$	591

At June 30, 2022, benefits payable for our Group and Specialty segment included IBNR of approximately $488 million, primarily associated with claims incurred in 2022.