Table:
|  |  | Years Ended December 31, |  |
| --- | --- | --- | --- |
| All figures in USD ‘000, except TCE rate per day | 2019 | 2018 | Variance |
| Voyage Revenue | 317,220 | 289,016 | 9.8% |
| Less Voyage expenses | (141,770) | (165,012) | (14.1%) |
| Net Voyage Revenue | 175,450 | 124,004 | 41.5% |
| Vessel Calendar Days (1) | 8,395 | 9,747 | (13.9%) |
| Less off-hire days | 293 | 277 | 5.8% |
| Total TCE days | 8,102 | 9,470 | (14.4%) |
| TCE Rate per day (2) | $21,655 | $13,095 | 65.4%) |
| Total Days for vessel operating expenses | 8,395 | 9,747 | (13.9%) |
Paragraphs:
(1) Vessel Calendar Days is the total number of days the vessels were in our fleet.
(2) Time Charter Equivalent (“TCE”) Rate, results from Net Voyage Revenue divided by total TCE days.
The change in Voyage revenue is due to two main factors:
i)  The number of TCE days
ii)  The change in the TCE rate achieved.
With regards to i), the decrease in vessel calendar days is mainly due to the disposal of ten vessels in 2018, offset by three 2018 Newbuildings delivered in the latter part of 2018.
With regards to ii), the TCE rate increased by $8,560, or 65.4%. The indicative rates presented by Clarksons Shipping increased by 91.7% for the twelve months of 2019 compared to the same twelve months in 2018 to $31,560 from $16,466, respectively. The rates presented by Clarksons Shipping were significantly influenced by the spike in the Suezmax tanker rates in the fourth quarter of both 2019 and 2018. Our average TCE was also positively impacted by the increased tanker rates towards the end of 2019, but not to the same extent as the rates reported by Clarksons Shipping. We expect this spike to materialize to a larger extent in the first quarter of 2020 compared to the rates reported by Clarksons Shipping.
As a result of i) and ii) net voyage revenues increased by 41.5% from $124.0 million for the year ended December 31, 2018, to $175.5 million for the year ended December 31, 2019.
Question:
What does Vessel Calendar Days refer to?
Answer: the total number of days the vessels were in our fleet.