BORROWINGS

Short-term debt

Short-term debt at December 31, 2018 and 2017, was as follows:



	December 31,
	2018				2017
	Amount		Rate		Amount		Rate
(amounts in thousands)
FHLB advances	$	1,248,070	2.62	%	$	1,611,860	1.47	%
Federal funds purchased	187,000		2.60	%	155,000		1.50	%
Total short-term debt	$	1,435,070			$	1,766,860

The following is a summary of additional information relating to Customers' short-term debt:



	December 31,
	2018			2017			2016
(amounts in thousands)
FHLB advances
Maximum outstanding at any month end	$	2,622,165		$	2,283,250		$	1,697,800
Average balance during the year	1,526,180			1,415,755			965,293
Weighted-average interest rate during the year	2.05		%	1.44		%	0.95		%
Federal funds purchased
Maximum outstanding at any month end	195,000			238,000			137,000
Average balance during the year	156,652			163,466			84,514
Weighted-average interest rate during the year	1.92		%	1.19		%	0.58		%

At December 31, 2018 and 2017, Customers Bank had aggregate availability under federal funds lines totaling $522.0 million and $310.0 million, respectively.

Long-term debt

FHLB advances

Customers had a total maximum borrowing capacity with the FHLB of $4.1 billion and with the FRB of $102.5 million at December 31, 2018. Customers had a total maximum borrowing capacity with the FHLB of $4.3 billion and with the FRB of $142.5 million at December 31, 2017. Amounts can be borrowed as short-term or long-term. As of December 31, 2018 and 2017, advances under these arrangements were secured by certain assets, which included qualifying loans of Customers Bank of $5.2 billion and $5.5 billion, respectively.

Senior notes

In July 2018, the 6.375% senior notes with an aggregate principal amount of $63.3 million issued by Customers Bancorp in July and August 2013 matured and were paid in full.

In June 2017, Customers Bancorp issued $100 million of senior notes at 99.775% of face value. The price to purchasers represents a yield-to-maturity of 4.0% on the fixed coupon rate of 3.95%. The senior notes mature in June 2022. The net proceeds to Customers Bancorp after deducting the underwriting discount and offering expenses were $98.6 million. The net proceeds were contributed to Customers Bank for purposes of its working capital needs and the funding of its organic growth.

On June 26, 2014, Customers Bancorp closed a private placement transaction in which it issued $25.0 million of 4.625% senior notes that will mature in June 2019. Interest is paid semi-annually in arrears in June and December.

Subordinated debt

On June 26, 2014, Customers Bank closed a private-placement transaction in which it issued $110.0 million of fixed-to-floating rate subordinated notes due in 2029. The subordinated notes bear interest at an annual fixed rate of 6.125% until June 26, 2024, and interest is paid semiannually. From June 26, 2024, the subordinated notes will bear an annual interest rate equal to three-month LIBOR plus 344.3 basis points until maturity on June 26, 2029. Customers Bank has the ability to call the subordinated notes, in whole or in part, at a redemption price equal to 100% of the principal balance at certain times on or after June 26, 2024. The subordinated notes qualify as Tier 2 capital for regulatory capital purposes.