SHORT-TERM BORROWINGS

Short-term borrowings are for terms under or equal to one year and are comprised of securities sold under REPOs and FHLB advances. All REPOs are overnight short-term investments and are not insured by the Federal Deposit Insurance Corporation, or FDIC. Securities pledged as collateral under these REPO financing arrangements cannot be sold or repledged by the secured party and, therefore, the REPOs are accounted for as secured borrowings. Mortgage-backed securities with amortized cost of $24.2 million and carrying value of $23.9 million at December 31, 2018 and amortized cost of $57.5 million and carrying value of $56.8 million at December 31, 2017 were pledged as collateral for these secured transactions. The pledged securities are held in safekeeping at the Federal Reserve. Due to the overnight short-term nature of REPOs, potential risk due to a decline in the value of the pledged collateral is low. Collateral pledging requirements with REPOs are monitored daily. FHLB advances are for various terms and are secured by a blanket lien on residential mortgages and other real estate secured loans.

The following table presents the composition of short-term borrowings, the weighted average interest rate as of December 31 and interest expense for the years ended December 31:



	2018						2017						2016
(dollars in thousands)	Balance		Weighted Average Interest Rate		Interest Expense		Balance		Weighted Average Interest Rate		Interest Expense		Balance		Weighted Average Interest Rate		Interest Expense
REPOs	$	18,383	0.46	%	$	222	$	50,161	0.39	%	$	54	$	50,832	0.01	%	$	5
FHLB advances	470,000		2.65	%	11,082		540,000		1.47	%	7,399		660,000		0.76	%	2,713
Total Short-term Borrowings	$	488,383	2.57	%	$	11,304	$	590,161	1.38	%	$	7,453	$	710,832	0.70	%	$	2,718