The following table summarizes the balance of our indebtedness as of December 31, 2016 and 2015 (in thousands):



	December 31, 2016			December 31, 2015
Principal amount	$	502,476		$	418,698
Less: unamortized discount and deferred loan costs⁽¹⁾	(2,292		)	(544		)
Carrying value	$	500,184		$	418,154

(1) Unamortized discount and deferred loan costs exclude net debt issuance costs related to establishing our unsecured credit facility. These costs are presented in the line item “Deferred loan costs, net” in the consolidated balance sheets.

The following table summarizes the components and significant terms of our indebtedness as of December 31, 2016 and 2015 (dollars in thousands):



	December 31, 2016					December 31, 2015
	Principal Amount		Unamortized Discount and Deferred Loan Costs			Principal Amount		Unamortized Discount and Deferred Loan Costs			Contractual Maturity Date		Stated Interest Rate⁽¹⁾			Effective Interest Rate⁽²⁾
Secured Debt
$60m Term Loan⁽³⁾	$	59,674	$	(204	)	$	60,000	$	(283	)	8/1/2019	⁽⁴⁾	LIBOR+1.90%			3.95	%
Gilbert/La Palma	2,909		(145		)	3,044		(153		)	3/1/2031		5.125	%	⁽⁵⁾	5.39	%
12907 Imperial Highway	5,182		180			5,299		303			4/1/2018		5.950	%	⁽⁶⁾	3.50	%
1065 Walnut Street	9,711		192			9,855		292			2/1/2019	⁽⁷⁾	4.550	%	⁽⁸⁾	3.54	%
Unsecured Debt
$100M Term Loan Facility	100,000		—			100,000		—			6/11/2019		LIBOR+1.50%		⁽⁹⁾	3.40	%	⁽¹⁰⁾
Revolving Credit Facility	—		—			140,500		—			6/11/2018	⁽⁴⁾	LIBOR+1.55%		^(9)(11)	2.32	%
$225M Term Loan Facility	225,000		(1,680		)	—		—			1/14/2023		LIBOR+1.75%		⁽⁹⁾	2.65	%
Guaranteed Senior Notes⁽¹²⁾	100,000		(635		)	100,000		(703		)	8/6/2025		4.290	%		4.36	%
Total	$	502,476	$	(2,292	)	$	418,698	$	(544	)


(1)	Reflects the contractual interest rate under the terms of the loan as of December 31, 2016.


(2)	Reflects the effective interest rate at December 31, 2016, which includes the effect of the amortization of discounts/premiums and deferred loan costs and the effect of interest rate swaps that are effective as of December 31, 2016.


(3)	This term loan is secured by six properties. Beginning August 15, 2016, monthly payments of interest and principal are based on a 30 years amortization table. As of December 31, 2016, the interest rate on this variable-rate term loan has been effectively fixed through the use of two interest rate swaps, one of which is an amortizing swap. See Note 7 for details.


(4)	One additional one-year extension available at the borrower’s option.


(5)	Monthly payments of interest and principal based on a 20-year amortization table.


(6)	Monthly payments of interest and principal based on a 30-year amortization table, with a balloon payment at maturity. We may prepay the loan in full during the 90 day period prior to the maturity date with without incurring prepayment penalties.


(7)	One additional five-year extension available at the borrower’s option. We may prepay the loan in whole at any time on or after November 1, 2018 through the initial maturity date without incurring prepayment penalties, subject to certain notice requirements.


(8)	Monthly payments of interest and principal based on a 25-year amortization table, with a balloon payment at maturity.


(9)	The LIBOR margin will range from 1.25% to 1.85% for the $100.0 million term loan facility, 1.30% to 1.90% for the unsecured revolving credit facility and 1.50% to 2.25% for the $225.0 million term loan facility depending on the ratio of our outstanding consolidated indebtedness to the value of our consolidated gross asset value, which is measured on a quarterly basis.


(10)	As of December 31, 2016, interest on the $100 million term loan has been effectively fixed through the use of two interest rate swaps. See Note 7 for details.


(11)	The facility additionally bears interest at 0.30% or 0.20% of the daily undrawn amount of the unsecured revolving credit facility if the balance is under $100 million or over $100 million, respectively.


(12)	Interest is payable semiannually on February 6 and August 6 of each year, beginning on February 6, 2016. We may prepay at any time all or, from time to time, any part of the notes, in amounts not less than $2.5 million of the notes then outstanding at (i) 100% of the principal amount so prepaid and (ii) the Make-Whole Amount (as defined in the credit agreement).