pre_text: RESULTS FROM VESSEL OPERATIONS During the year ended December 31, 2019, shipping revenues decreased by $10,616 or 2.9% compared to 2018. The decrease primarily resulted from three fewer vessels in operation during most of 2019 compared to 2018 and one less Government of Israel voyage in 2019 compared to 2018. This decrease was partially offset by the addition of two new vessels to our fleet at the beginning of the fourth quarter of 2019. Reconciliations of TCE revenues, a non-GAAP measure, to shipping revenues as reported in the consolidated statements of operations follows: Consistent with general practice in the shipping industry, we use TCE revenues, which represents shipping revenues less voyage expenses, as a measure to compare revenue generated from a voyage charter to revenue generated from a time charter. TCE revenues, a non-GAAP measure, provides additional meaningful information in conjunction with shipping revenues, the most directly comparable GAAP measure, because it assists management in decisions regarding the deployment and use of our vessels and in evaluating their financial performance.
table: Years Ended December 31,
table: 2019 2018
table: Time charter equivalent revenues $335,133 $326,707
table: Add: Voyage expenses 20,414 39,456
table: Shipping revenues $355,547 $366,163
question: Analyse this data from a financial earnings document. What is the change in Add: Voyage expenses from Years Ended December 31, 2018 to 2019?