pre_text: GreenSky, Inc. NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued) (United States Dollars in thousands, except per share data, unless otherwise stated) Key details of the term loan are as follows: (1) The principal balance of the term loan is scheduled to be repaid on a quarterly basis at an amortization rate of 0.25% per quarter through December 31, 2024, with the balance due at maturity. For each of the next five years, principal repayments on the term loan are expected to be $4,000. (2) For the years ended December 31, 2019 and 2018, debt discount of $613 and $593, respectively, and debt issuance costs of $1,062
  and $1,091, respectively, were amortized into interest expense in the Consolidated Statements of Operations. Giving effect to the
  amortization of debt discount and debt issuance costs on the term loan, the effective interest rates were 5.95% and 5.99% during the
  years ended December 31, 2019 and 2018, respectively.
table: December 31,
table: 2019 2018
table: Term loan, face value(1) $393,000 $397,000
table: Unamortized debt discount (2) (3,115) (3,728)
table: Unamortized debt issuance costs(2) (5,388) (6,450)
table: Term loan $384,497 $386,822
question: Analyse this data from a financial earnings document. What was the change in the Unamortized debt discount between 2018 and 2019?