In connection with our recognition of an allowance for credit losses for reinsurance-related assets, we perform a quantitative analysis using a probability of loss approach to estimate expected credit losses for reinsurance recoverables, inclusive of similar assets recognized using the deposit method of accounting. As of June 30, 2021, our allowance for credit losses for reinsurance-related assets was $196 million. There have been no material changes to the allowance for credit losses for the six months ended June 30, 2021.

Some portions of our annuity business have been reinsured on a Modco basis with other companies. In a Modco agreement, we as the ceding company retain the reserves, as well as the assets backing those reserves, and the reinsurer shares proportionally in all financial terms of the reinsured policies based on their respective percentage of the risk. Effective October 1, 2018, we entered into one such Modco agreement with Athene Holding Ltd. (“Athene”) to reinsure fixed annuity products, which resulted in a deposit asset of $5.4 billion and $5.8 billion as of June 30, 2021, and December 31, 2020, respectively, within other assets on our Consolidated Balance Sheets.

We held assets in support of reserves associated with the transaction in a Modco investment portfolio, which consisted of the following (in millions):


	As of			As of
	June 30,			December 31,
	2021			2020
Fixed maturity AFS securities		$	1,235		$	1,531
Trading securities			3,125			3,357
Equity securities			20			17
Mortgage loans on real estate			818			832
Derivative investments			103			103
Other investments			299			167
Cash and invested cash			182			92
Accrued investment income			41			42
Other assets			13			3
Total		$	5,836		$	6,144

In addition, the portfolio was supported by $175 million of over-collateralization and a $159 million letter of credit as of June 30, 2021.